docs: close Phase 8 integration

docs/screenshare-audio-exclusion-impl-plan.md

@@ -22,8 +22,10 @@ validated and committed locally in PixelPass (`7b11827`).** The deterministic Ph
 link-manager matrix is complete. **The production-path three-arm AEC leak qualification is
 built, validated and committed locally in PixelPass (`e027bc6`), completing Phase 6.**
 **Phase 7's public selector, AEC wiring and versioned capability response are built, validated
-and committed locally in PixelPass (`792f2bd`).** Phases 8–9 are not built — nothing released to
-date changes the feature's user-visible behaviour. **Phase 8 is now the current front.**
+and committed locally in PixelPass (`792f2bd`).** **Phase 8's PeerSpeak capability negotiation,
+picker/argv integration and causal status surface are built, validated and committed locally
+(`2c2b861`).** Phase 9 remains unbuilt; nothing has been released. **Phase 9 is now the current
+front and remains the ship gate.**
 **Date:** 2026-07-21 (v4); status line refreshed 2026-08-21
 **Design of record:** [`screenshare-audio-exclusion-plan.md`](screenshare-audio-exclusion-plan.md) v3.8, round 11.
 **Scope:** *ordering, gates and acceptance criteria only.*
@@ -968,6 +970,35 @@ variant names (0d) do not block on it.
 - Capability-gated picker entry; wording per v3.4 §11.
 - Regression: existing `--app` / `--strict-audio` argv byte-identical to today.
 
+> **Phase 8 — built, validated and committed locally as PeerSpeak `2c2b861` on 2026-08-21.**
+> The picker/core boundary now uses one typed selection for legacy desktop, desktop-excluding,
+> and strict per-app audio. `System audio except PeerSpeak` appears only when the exact resolved
+> PixelPass advertises `desktop_audio_exclusion`; the existing `All system audio` choice remains
+> alongside it with its echo warning. The machine-readable schema is primary, `--help` is only
+> the old-PixelPass strict-app fallback, and the two capability bits stay independent.
+>
+> Capability results carry the resolved executable path. A capability-gated share reuses the
+> picker probe only for that same path; a changed override or `$PATH` resolution is re-probed at
+> start and fails closed when the selected feature is absent. The new mode emits exactly
+> `--audio-mode=desktop-excluding` plus `--aec=off|pulse-module:<idx>`. The session-owned
+> `EchoCancelGuard` exposes its verified numeric module index without moving the guard out of the
+> load-bearing teardown object. Legacy desktop and per-app argv still delegate to the old builder
+> and are byte-identical.
+>
+> All four version-1 exclusion events parse into one shared status type that crosses the actual
+> host-notice channel into `UiEvent`; there is no duplicate matching enum. The UI retains an
+> explanatory warning even when a status races the share-start acknowledgement, displays it with
+> the live sharing badge, clears it on stop, and ignores late events for another mode. Exact
+> parser and causal tests cover `stream_unsupported`, `aec_failed`, `aec_revoked`, and
+> `foreign_aec_warning`.
+>
+> Final serialized validation (used after the parallel all-target link exhausted disk) passes:
+> 649 unit tests with 7 live-only ignored, 20 integration tests with 4 live-only screen-share
+> gates ignored, strict all-target Clippy, formatting, and `git diff --check`. The host-fault
+> integration target compiles with the typed command. PixelPass's completed 9.1 GiB target tree
+> was cleaned to recover disk; no source or Git state was removed. Phase 9 remains the explicit
+> rig-upgrade and two-machine field-test ship gate.
+
 ---
 
 ## 7. Phase 9 — rig upgrade and field tests 🚦 SHIP GATE