Closes review round 2 — 1 blocking, 2 high, 1 medium — decides both
remaining open items, and re-integrates canonical `main` @ `ccf29e3`
(#172 + #157; documentation plus one `src/buffer.rs` regression test,
no protocol or Stage 2 source anchor moved).
**R2-1 (blocker) — the seam is three boundaries, not one.** Rev 2 asked
for a single document-bottom accessor. That is wrong: once a panel is
installed the present single value must DIVERGE, because several of its
consumers must not move at all. `text_area_bottom`
(`pmacs-gpu/src/main.rs:8490`) is today `status_band_top`,
`geometry_capacity_bottom`, and `document_text_bottom` at once. Rev 3
defines all three, classifies every one of its ~19 call sites as
status-owned / document-owned / geometry, and records that four sites
rev 2 named (`:3175`, `:3185`, `:6601`, `:6607`) consume a status-band
HEIGHT and no bottom coordinate at all, while the status background
`:5908` and status text `:7134`/`:7922` must stay at the physical
window bottom.
The acceptance is now a contrast assertion: installing a panel moves
every document-owned consumer WHILE the status band stays
pixel-identical. "Everything moved" alone is passed by a blanket
rewrite of the helper, which is exactly the wrong implementation.
**R2-2 (high) — epoch exactness.** `accept_frame_geometry` returns
`Advanced | Duplicate | Rejected` instead of a boolean that cannot
separate reconcile-needed from already-current from stale; if a boolean
is ever kept internally it must be named `advanced`, since `Duplicate`
is also accepted. Rev 2's exhaustion wording permitted retaining stale
geometry, which is not fail-closed — a real resize after exhaustion
would keep painting a panel sized to disowned geometry. The grid path
now clears `frame_geometry` to unknown and reconciles hidden, and the
frontend takes a terminal latch so a retained matching `Present` cannot
resurrect the band; only a fresh session clears it.
**R2-3 (high) — parent acceptance 52 splits.** 2A has no semantic panel
projection, so it can only prove the extracted painter honors an
explicit `None` map plus the `src/window.rs:562` comment fix. The real
contract is production-reachable only in 2B and is reasserted there
beside 42/43/44.
**R2-4 (medium) — touched gates named**: `statusline_segments_acceptance`,
`m11_5_semantic_acceptance`, `gpu_initial_target_acceptance`,
`gpu_font_acceptance`, beside the vterm, folding, and GPU suites.
Open items decided: `BASE_DIVIDER_HEIGHT = 4.0` at scale 1.0, scaled by
`FontMetrics::scale`, whole strip painted `ui.divider` and used as the
exact hover/drag hit rect; `TEXT_TOP` stays `16.0` unscaled, with
Q#BP15a's "all quantities use the frontend's current scale" narrowed to
font-derived metrics and the divider. Wholesale surface-inset/DPI
scaling is recorded as separate work, not smuggled in.
The ledger's bottom-panel lane keeps its census correction and gains
the three-boundary one.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>