Record second GPU invocation review closure

Advance the framing to Revision 6 and record the strengthened non-CRDT,
Ctrl-C, strict-operand, probe-throttling, and PID-cleanup contracts. Update the
durable and volatile checkpoints to implementation commit 154cb9f.

docs/active-work.md

@@ -57,18 +57,21 @@ If it does not, stop and repair the remote/fetch configuration.
 - Portable branch: `githubsucks/gpu-invocation`
 - Pull request: **#141 OPEN — do not merge without explicit user approval.**
 - Base: `githubsucks/main` @ `96d0bae`; protocol remains v19.
-- Implementation checkpoints: `69825d0` (exception-safe immediate reaper
-  ownership) atop `82355ca` (first implementation-review fixes) and
-  `6fd5834`; approved framing began at `821835b` and is now Revision 5.
-- State: all six implementation-review findings are resolved, all 18
-  acceptance criteria complete, and the PR awaits another user review. Public
-  path is additive `pmacs --gpu [--socket NAME|PATH]`; bare `pmacs [FILE]`
-  remains TUI and `pmacs --gpu FILE` remains rejected.
+- Implementation checkpoints: `154cb9f` (second implementation-review fixes)
+  atop `69825d0` (exception-safe immediate reaper ownership), `82355ca`
+  (first implementation-review fixes), and `6fd5834`; approved framing began
+  at `821835b` and is now Revision 6.
+- State: both implementation reviews are resolved, all 18 acceptance criteria
+  complete, and the PR awaits user review. Public path is additive
+  `pmacs --gpu [--socket NAME|PATH]`; bare `pmacs [FILE]` remains TUI and
+  `pmacs --gpu FILE` remains rejected.
 - Review fixes: pre-state GPU events are buffered until winit state exists;
-  daemon stderr is detached; spawned-child ownership is handed off without a
-  leak window; direct CLI guidance, help operands, and sibling-file discovery
-  are strict; transient retry, timeout reporting, hermetic socket paths, and
-  deterministic concurrent-loser reaping have behavioral coverage.
+  daemon stdio is detached; spawned-child ownership is handed off without a
+  leak window; direct CLI guidance, help/path operands, and sibling-file
+  discovery are strict; transient retry, timeout reporting, hermetic socket
+  paths, deterministic concurrent-loser reaping, pre-I/O non-CRDT gating, and
+  post-SIGINT use of a pre-attached frontend have behavioral coverage. Probe
+  disconnect polling remains bounded and cleanup skips already-reaped PIDs.
 - Verification: strict workspace and CRDT acceptance Clippy; 1,768 default +
   1,944 CRDT library tests; root CLI 33; GPU 149 required; GPU invocation
   acceptance 1 default + 9 CRDT; Vterm Stage 3 7; M4 121 with 3 ignored and

docs/agent-handoff.md

@@ -24,8 +24,8 @@ commands, read `docs/active-work.md` immediately after this file.
   `ThemeFacts`, v17 = `FontFacts`, v18 = `StatuslineSegments`, v19 = terminal
   frames/events).
 - **One-command GPU invocation is implemented on OPEN PR #141, not yet on
-  `main`** (`gpu-invocation`, final implementation-review checkpoint
-  `69825d0`, framing Revision 5). The additive public path is
+  `main`** (`gpu-invocation`, second implementation-review checkpoint
+  `154cb9f`, framing Revision 6). The additive public path is
   `pmacs --gpu [--socket NAME|PATH]`; bare `pmacs [FILE]` remains the TUI.
   Root owns the CRDT gate, socket resolution, sibling-regular-file GPU
   discovery/PATH fallback, and GPU outcome. The separate `pmacs-gpu` binary

docs/gpu-invocation-framing.md

@@ -1,7 +1,7 @@
 # GPU invocation — one-command broker framing
 
-**Revision 5 — implementation review complete on `gpu-invocation`. Ground
-truth: canonical `main` @ `96d0bae`, protocol v19, 2026-07-23.**
+**Revision 6 — second implementation review complete on `gpu-invocation`.
+Ground truth: canonical `main` @ `96d0bae`, protocol v19, 2026-07-23.**
 
 The GPU editor works, but reaching it is still a development-session ritual:
 build two packages with different feature requirements, keep a foreground
@@ -42,6 +42,12 @@ inherits no launcher stdio. Direct GPU help points normal users to the root
 broker and labels raw socket attach as advanced. The retry, timeout, socket
 type, and concurrent-loser contracts now have deterministic behavioral tests.
 
+Revision 6 closes the remaining non-blocking review findings. The managed
+probe throttles after its event channel disconnects; option-like path operands
+are rejected; cleanup never signals an already-reaped daemon PID; and the
+acceptance suite now proves both pre-I/O non-CRDT gating and post-SIGINT use of
+a frontend attached before the launcher exits.
+
 ## Ground truth
 
 ### Current user path
@@ -550,9 +556,10 @@ Vterm probe continues to cover offscreen wgpu.
    argument named. Bare `pmacs --socket research` (with or without a local
    file / `-nw`) exits 2 and says which owning mode is required.
 2. **Non-CRDT build fails before socket or spawn:** a default-feature
-   `pmacs --gpu` names `--features crdt`; a capable daemon already listening
-   does not weaken the gate, and fake GPU/daemon executables record zero
-   invocations. The default socket remains unowned.
+   `pmacs --gpu` names `--features crdt`, invokes no GPU executable, and leaves
+   the default socket absent under a private runtime directory. Repeating the
+   command against an already-listening Unix socket neither invokes the GPU
+   nor disturbs that socket, proving the gate precedes socket I/O.
 3. **Sibling discovery wins:** with executable fixtures at the current-exe
    sibling and on PATH, the sibling regular file receives the managed
    arguments. A directory at the sibling pathname is ignored in favor of
@@ -566,12 +573,14 @@ Vterm probe continues to cover offscreen wgpu.
    handshake, receives the first `BufferSnapshot`, and leaves the daemon
    connectable after the probe exits.
 6. **Ctrl-C does not kill the daemon:** spawn the managed probe/broker in its
-   own process group, wait for the probe's `phase=ready`, attach a second real
-   frontend, then simulate terminal Ctrl-C with `kill(-pgid, SIGINT)`. Assert
-   the launcher/frontend exit while the separately grouped daemon and second
-   session remain usable. This does not require a controlling terminal or a
-   foreground-process-group claim in CI. Direct foreground `pmacs --daemon`
-   still exits cleanly on SIGINT.
+   own process group, wait for the probe's `phase=ready`, and complete a second
+   real frontend's handshake and initial snapshot/grid sync before simulating
+   terminal Ctrl-C with `kill(-pgid, SIGINT)`. After the launcher/frontend
+   exits, resize the pre-existing second frontend and require its full-grid
+   response; the separately grouped daemon and existing session remain usable.
+   This does not require a controlling terminal or a foreground-process-group
+   claim in CI. Direct foreground `pmacs --daemon` still exits cleanly on
+   SIGINT.
 7. **Concurrent launchers converge:** hold two daemon wrappers behind a shared
    barrier so both managed probes authorize and spawn before either daemon
    binds the absent named socket. Exactly one daemon owns the lock; both
@@ -615,9 +624,10 @@ Vterm probe continues to cover offscreen wgpu.
     direct `--attach PATH` as advanced. Existing `--headless-probe SOCKET
     REPORT` and hidden `--headless-managed-probe SOCKET REPORT DAEMON_EXE`
     accept exactly their operands. Missing/trailing/unknown/incomplete args
-    exit 2; trailing help/version operands say those flags accept no operands.
-    `--version` prints package and protocol versions without initializing
-    winit/wgpu.
+    exit 2; trailing help/version operands say those flags accept no operands;
+    option-like path operands are rejected and require an explicit `./`
+    prefix when they name a real relative path. `--version` prints package and
+    protocol versions without initializing winit/wgpu.
 16. **Existing direct and Vterm paths remain intact:** rebuilt
     `pmacs-gpu --attach RAW_PATH` still renders an existing CRDT daemon, and
     `tests/vterm_stage3_acceptance.rs` still invokes its unchanged
@@ -652,13 +662,16 @@ Vterm probe continues to cover offscreen wgpu.
   protocol/capability failures never authorize replacement.
 - `--headless-managed-probe SOCKET REPORT DAEMON_EXE` drives the production
   managed connector, writes atomic `phase=ready` / `phase=complete` reports,
-  holds on stdin, and exposes disconnect plus daemon-reaper observations.
-- `tests/gpu_invocation_acceptance.rs` covers the root broker, non-CRDT gate,
-  existing/missing/stale/racing daemon paths, process-group SIGINT isolation,
-  capability and protocol mismatches, bounded startup failure, deterministic
-  losing-child reaping, outcome propagation, and strict headless CLI behavior.
+  holds on stdin, exposes disconnect plus daemon-reaper observations, and
+  retains its 50-ms cadence after the event channel closes.
+- `tests/gpu_invocation_acceptance.rs` covers the root broker, pre-I/O
+  non-CRDT gate, existing/missing/stale/racing daemon paths, process-group
+  SIGINT isolation with a pre-attached surviving frontend, capability and
+  protocol mismatches, bounded startup failure, deterministic losing-child
+  reaping without signaling freed PIDs, outcome propagation, and strict
+  headless CLI behavior.
 
-Verification on 2026-07-23 after the implementation review:
+Verification on 2026-07-23 after the second implementation review:
 
 - root CLI unit suite: 33 passed;
 - required GPU suite: 149 passed;