docs: record Phase 7 resilience state and re-scope

docs/PHASES.md

@@ -82,16 +82,24 @@ discovered addresses in reachability order (private IPv4 first).
 
 ## Phase 7 — Resilience and Polish
 
-**Goal**: loss recovery, hardware acceleration, and packaging.
+**Goal**: loss recovery, hardware acceleration, and polish.
 
-- NACK / PLI feedback loop.
-- Jitter buffer on the receiver.
-- VAAPI/NVENC hardware encode probes and fallback.
-- Optional GUI target behind `meson -Dgui=true`.
-- `.desktop` file, icon, packaging notes.
+- [x] PLI keyframe feedback over signaling (receiver asks, sender
+      re-encodes a keyframe; validated end-to-end with an induced loss).
+- [x] Jitter/reorder window on the receiver (16 packets / 60 ms).
+- [x] Hardware H.264 decode probe with software fallback (h264_v4l2m2m —
+      the Pi's VideoCore path; --swdecode opts out).
+- [ ] GTK4 sender GUI behind `meson -Dgui=true` + a waybar widget
+      (requested; plan approved scope: sender panel, state file,
+      `screencast waybar` subcommand).
+- [ ] VAAPI hardware encode probe on the sender (deferred: software
+      encode is not the bottleneck).
+- Deferred: .desktop file, packaging.
 
 **Validation**: sustained streaming under packet loss; hardware accel smoke
-where available.
+where available. PLI + jitter validated on the desktop (induced-loss probe);
+hardware decode validated as clean-fallback on the desktop, hardware path
+pending a run on the Pi.
 
 ## Current phase