docs(framing): revision 20 --- three blockers from review

The verification base still said `72da24a` in three live places: the
§2 header's "Verification base" line, §2a's own heading, and §1b's
blockquote. All three now name `0ec13b3` while preserving `72da24a` as
the original measurement.

The live panel-replay section still contradicted the discharge --- it
said 1b "does not ship before" the prerequisite, "depends on that
lane", that vertical panel scrolling is "equally dead today", and it
repeated the three-step future ordering. The ruling and its two reasons
are now marked as made-and-carried-out; steps 1 and 2 are struck as
done; step 3 stands.

And the conceptual point behind that, which I had wrong: #243
discharges the PREREQUISITE completely within its scope and supplies
the vertical RECEIVER path. It discharges NONE of B1's witness, on
either axis, because B1's producer --- a per-surface fractional
accumulator --- is new and no #243 test exercises it. A vertical panel
wheel routed through a new accumulator can drop sub-ticks or carry
residue across a surface switch. Implementation already present is not
evidence already owed, and saying "#243 discharges the vertical half of
the witness" conflated the two.

The sweep also verified RANGE, not IDENTITY, which is the weaker check.
Six citations landed in the right file and the wrong construct: B4's
`UnusedButton`/`route_pointer`, misfiled against editor.rs when they are
main.rs; the panel paint call; `OwnCursor`'s type doc against its field;
the GPU wrap branch against the `horizontal_follow` call; and
`scroll_top`'s zeroing, one line before the residual's. Every live
citation is now checked against the construct its prose names.

docs/gui-stage1-input-framing.md

@@ -32,19 +32,34 @@ which §2a's own history predicted would happen.
   this base**: the dispatcher is split into `classify_panel_pointer`
   (`src/editor.rs:2985`) and `apply_panel_pointer` (`:3088`), and the
   vertical axis replays for real at `:3277`–`:3278`. **The prerequisite
-  is DISCHARGED.** What does not lapse is the witness: 1b still owes an
+  is DISCHARGED** — completely, within its scope, and it supplies the
-  end-to-end panel-wheel **effect** witness on **both** axes, of which
+  vertical receiver path. **It discharges none of B1's witness**: 1b
-  #243 discharges only the vertical half.
+  still owes an end-to-end panel-wheel **effect** witness on **both**
+  axes, because B1's fractional accumulator is NEW and no #243 test
+  exercises it. Implementation already present is not evidence already
+  owed.
 
 **Citation policy, applied throughout:** a citation that makes a claim
-about the tree **as it is** was re-measured and renumbered — 45 of
+about the tree **as it is** was re-measured and renumbered — 45 in the
-them. A citation that records **what an earlier revision cited** is
+first pass, plus **six the first pass got wrong**. A citation that records **what an earlier revision cited** is
 left exactly as written and its block is labelled *"citations are
 HISTORICAL (`72da24a`)"*. Renumbering those would have falsified
 sentences whose whole point is that an earlier citation was wrong.
 
+**The first pass verified RANGE, not IDENTITY, and that was the wrong
+check.** Every citation landed inside its file, and six still pointed at
+the wrong construct: B4's `UnusedButton`/`route_pointer` (`:3803`,
+`:3811`, misfiled against `editor.rs` when they are `main.rs`), the
+panel paint call (`src/editor.rs:2863`), `OwnCursor`'s **type doc**
+(`:2448`) as against its field (`:1774`), the GPU **wrap branch**
+(`:8120`) as against the `horizontal_follow` call (`:8089`), and
+`scroll_top`'s zeroing (`:6217`), which sits one line before the
+residual's. **Every live citation is now identity-checked against the
+construct its prose names**, not merely bounds-checked.
+
 **No ruling changes in revision 20.** It is a re-measurement, three
-corrections, and a discharge.
+corrections, a discharge, and one conceptual separation — implementation
+already present is not evidence already owed.
 
 **Previously, revision 19 — RECONCILES TWO LINEAGES THAT BOTH NUMBERED
 THEMSELVES 13.** This document was advanced independently by two
@@ -240,10 +255,15 @@ and it lands ahead of 1e because panel-pointer replay blocks 1b.
 Protocol slices stay serialized; one was inserted in front.
 `ADVERTISED_PROTOCOL_VERSION` remains pinned at **20**.
 
-**Verification base:** §2 is **re-measured at `4f77491`** (2026-08-12),
+**Verification base: `0ec13b3`** (revision 20). §2 was re-measured at
+`4f77491` (2026-08-12) and §2a **originally** at `72da24a`
+(2026-08-13); both are historical anchors now, kept so the
+re-measurements can be checked against what they replaced.
+§2 is **re-measured at `4f77491`** (2026-08-12),
 the tip after 1-pre; it was originally taken at `a994f37`. **§2a is
-measured at `72da24a`** (2026-08-13), the tip after 1a and #240, and it
+measured at `0ec13b3`** (revision 20) — originally at `72da24a`
-is the base for **1b only**; it carries Q#S1-11's ruling. Sections
+(2026-08-13), the tip after 1a and #240 — and it is the base for **1b
+only**; it carries Q#S1-11's ruling. Sections
 other than §2/§2a were written against `a994f37` and their *rulings*
 are unaffected by 1-pre, which changed no behaviour — but **any line
 number outside §2 and §2a
@@ -336,7 +356,7 @@ survives A4**: a native close still returns `Exit`, and
 keyboard input is truncated to its first scalar, and an IME commit
 produces nothing.
 
-## 2a. Ground truth for 1b — MEASURED at `72da24a` (2026-08-13)
+## 2a. Ground truth for 1b — RE-MEASURED at `0ec13b3` (revision 20); originally at `72da24a` (2026-08-13)
 
 §2 above was measured for **1a**, at `4f77491`. 1a (#239) has since
 merged and #240 landed on top, so **every coordinate the 1b table cites
@@ -471,7 +491,7 @@ minimap do not get replaced — their state OUTLIVES the buffer.** A
 panel or terminal residual can be keyed to a surface that goes away; the
 document's and the minimap's live in the long-lived GPU `State`, which
 survives a buffer switch. **Their reset is manual, and there is a list
-to be forgotten from.** Buffer replacement (`pmacs-gpu/src/main.rs:6218`
+to be forgotten from.** Buffer replacement (`pmacs-gpu/src/main.rs:6217`
 onward) zeroes `scroll_top`, `code_scroll_residual` and
 `code_scroll_left` **one explicit line at a time**, each with its own
 comment — including `code_scroll_left`, added later precisely because a
@@ -557,10 +577,10 @@ remains is narrower and was already assigned here: **the horizontal
 document-panel leg is B1–B3's**, per the "Panel-replay consequence"
 paragraph in §1b.
 
-**Ruling: 1b does not absorb it, and 1b does not ship before it.** The
+**Ruling as made (historical): 1b does not absorb it, and 1b does not
-replay is repaired in a **prerequisite lane** carrying parent
+ship before it.** The replay was to be repaired in a **prerequisite
-acceptance 48, and **1b depends on that lane** — see the ordering
+lane** carrying parent acceptance 48, with **1b depending on that
-below. Two reasons, and the one revision 15 gave was wrong:
+lane**. Two reasons were given, and the one revision 15 gave was wrong:
 
 1. **Replay is broader than 1b, and already owned.** Acceptance 48
    (`docs/bottom-panel-framing.md:1719`) has `PanelPointer` driving
@@ -569,9 +589,15 @@ below. Two reasons, and the one revision 15 gave was wrong:
    activation ordering and coalescing rules. A wheel is one gesture in
    that set. Implementing it alone from an input slice would deliver a
    fragment of an acceptance criterion owned elsewhere.
-2. **The defect predates 1b** and is not horizontal-specific: vertical
+2. **The defect predates 1b** and was not horizontal-specific:
-   panel scrolling is equally dead today. A fix belongs where the
+   vertical panel scrolling was **equally dead at `72da24a`**. A fix
-   contract lives, not bolted to the slice that happened to find it.
+   belongs where the contract lives, not bolted to the slice that
+   happened to find it.
+
+**STATUS AT `0ec13b3`: the ruling was carried out and the dependency is
+DISCHARGED.** #243 was that prerequisite lane, it merged, and this base
+contains it. The two reasons above are why the work went there rather
+than here; they are not live obligations.
 
 **Revision 15 said "it is not input work". That was wrong** — replay
 includes terminal mouse reporting and click-to-focus, which is exactly
@@ -585,18 +611,36 @@ works and cannot see the half that does not — *it reproduces the blind
 spot that let this sit undetected.* Passing panel rows would again mean
 nothing about whether a panel wheel scrolls.
 
-So the dependency is **hard, and ordered**:
+**Steps 1 and 2 are DONE. Step 3 is 1b's, undiminished.**
 
-1. **The replay lane merges first.**
+1. ~~The replay lane merges first.~~ **#243 merged.**
-2. **1b rebases onto it**, and its base moves from `72da24a` to that
+2. ~~1b rebases onto it.~~ **Done: 1b's base is `0ec13b3`**, which
-   merge commit. §2a's other measurements are unaffected — the replay
+   contains #243. §2a's other measurements were unaffected by that
-   lane touches the daemon side.
+   lane, as predicted — it touched the daemon side.
 3. **1b carries an END-TO-END panel-wheel EFFECT witness, on BOTH
    axes**: a wheel over a panel cell moves that panel's viewport
    vertically, and a horizontal wheel moves it horizontally. Not "a
-   `PanelPointer` was emitted" — the observable effect. The horizontal
+   `PanelPointer` was emitted" — the observable effect.
-   leg is not optional garnish: it is the axis with **no handler at
+
-   all**, which is exactly where the emit-and-discard defect lived.
+**Why BOTH axes are still owed, when #243 already supplies the vertical
+receiver.** These are different things and revision 20's first draft
+conflated them:
+
+- **The receiver path** for a vertical panel wheel exists now
+  (`src/editor.rs:3277`–`:3278`). That is implementation, and #243
+  discharges it completely within its scope;
+- **B1's evidence** is not discharged by any of it, on either axis,
+  **because B1's producer is NEW**. 1b introduces a per-surface
+  fractional residual accumulator that did not exist when #243 was
+  written and that no #243 test exercises. A vertical panel wheel
+  routed through a new accumulator can fail in ways the old whole-tick
+  path could not — dropped sub-ticks, residue carried across a surface
+  switch, a residual keyed to a panel that is gone.
+
+So: **#243 discharges the PREREQUISITE. It discharges none of the
+WITNESS.** The horizontal leg additionally has no handler at all, which
+is where the emit-and-discard defect lived — but the vertical leg is
+owed for its own reason, not as a formality.
 
 **Panel inertness is therefore NOT an option and is not claimed.** The
 panel's contract is "emit both axes with its own residual, and the
@@ -625,10 +669,10 @@ contracts are unaffected; the **implementation shape** is.
   written as a separate site would be **clobbered by that else branch**.
   B5 must extend this function, not join it.
 - **B4 — "no middle-click path".** 1-pre already built the landing
-  site and named this row in it: `PointerRoute::UnusedButton` (`:3623`)
+  site and named this row in it: `PointerRoute::UnusedButton` (`:3803`)
   is documented *"Stage 1b's B4 gives the middle button a meaning
   (PRIMARY-selection paste on Linux) and lands here."* `route_pointer`
-  (`:3631`) sends every non-left, non-right-press button there. B4
+  (`:3811`) sends every non-left, non-right-press button there. B4
   splits a variant that already exists.
 
 ### CORRECTION 4 — B7 re-opens a deferred question, and the table does not say so
@@ -668,7 +712,7 @@ the GPU's `horizontal_follow` (`:8117`) has the same shape.
 **And it happens on the next PAINT, not the next caret event.**
 `prepare_window_cursor_visible` (`src/editor.rs:5256`) calls
 `horizontal_follow` unconditionally as its **first** act (`:5277`), and
-`paint_frame` (`:5485`) calls it every frame (`:5590`, and `:2572` for
+`paint_frame` (`:5485`) calls it every frame (`:5590`, and `:2863` for
 the panel). Revision 13 said "the next caret event"; that was wrong and
 understated the exposure — the origin is overwritten by a redraw with
 no input at all.
@@ -682,7 +726,8 @@ viewport that is overwritten on the next frame.
 **(A) is not viable in 1b, and the vertical precedent does not reach
 it.** `scroll_window` carries point because it is **TUI-side**, where
 the editor owns the cursor directly. The GPU has no such power:
-`OwnCursor` (`pmacs-gpu/src/main.rs:1774`) is *"pmacs-gpu's own cursor
+`OwnCursor` (type doc `pmacs-gpu/src/main.rs:2448`; the field is
+`:1774`) is *"pmacs-gpu's own cursor
 position, **mirrored** from `CursorByte`"* — a read-only reflection of
 daemon state. The only wire operation that positions it is `Pointer`,
 and `dispatch_pointer` (`src/editor.rs:4376`) sets `active_frontend`,
@@ -721,7 +766,8 @@ undefined, which is the part that decides whether the feature works.
    *changing*, never by elapsed time or by the follow running.
 5. **Wrap and buffer replacement clear it and pin the origin to zero.**
    This is the existing rule (`horizontal_follow`'s wrap branch, and
-   the GPU's at `:8089`); authority must not survive either.
+   the GPU's wrap branch at `:8120`; `:8089` is only the
+`horizontal_follow` call); authority must not survive either.
 
 ##### What B7 and B3 must witness
 
@@ -876,13 +922,19 @@ panel-wheel replay (`:3277`–`:3278`). **1b has no outstanding
 prerequisite**, and the rebase this revision was written on is the one
 the order below called for.
 
-**What does NOT lapse is the witness.** The reason for demanding it
+**What does NOT lapse is the witness, on EITHER axis.** The reason for
-stands unchanged: 1b's B1 makes the panel a first-class wheel target
+demanding it stands unchanged: 1b's B1 makes the panel a first-class
-with its own residual, and **the original defect was exactly "frontend
+wheel target **with its own residual**, and **the original defect was
-emits, receiver discards"** — so a 1b that witnessed emission alone
+exactly "frontend emits, receiver discards"** — so a 1b that witnessed
-would repeat the blind spot that hid it. **1b still owes an end-to-end
+emission alone would repeat the blind spot that hid it.
-panel-wheel EFFECT witness on BOTH axes**, and #243 discharges only the
+
-vertical half of what that witness must show.
+**#243 supplies the vertical RECEIVER; it does not supply B1's
+EVIDENCE.** B1's producer — a per-surface fractional accumulator — did
+not exist when #243 was written, and no #243 test exercises it. So
+**1b owes the end-to-end effect witness on BOTH axes**: the horizontal
+leg because it has no handler at all, and the vertical leg because it
+now runs through a new accumulator that can drop sub-ticks or carry
+residue across a surface switch.
 
 **Order, as it now stands: the prerequisite is met; 1b implements
 B1–B7 on this base and lands the both-axis effect witness.** 1b's base
@@ -1077,9 +1129,12 @@ The crate has **exactly one** executable `event_loop.exit()`, in
 
 ### 1b — pointer and scroll
 
-> **Read §2a first, and note that it CHANGES two of these rows.** Every
+> **Read §2a first, and note that it CHANGES two of these rows.** §2a
+> is measured at **`0ec13b3`**; the line numbers it replaced were
+> `72da24a`-era. Every
 > line number below was measured before 1-pre and is stale. §2a
-> re-measures them at `72da24a`; records three rows whose "nothing
+> re-measures them — at `72da24a` when this note was written, and at
+> `0ec13b3` since revision 20; records three rows whose "nothing
 > exists yet" is wrong (B3, B4, B5); **replaces B1's undefined
 > "surface" with a normative six-target enumeration**; **replaces B3's
 > "content bounds" with B7's exact saturated upper bound**; and rules