feat(gui): system-tray applet (M11) + GUI smoke tests — 0.19.0

QSystemTrayIcon applet (gui/tray.py, D13): menu with live CPU/GPU temp + memory
used/total, a status line, a Run Diagnostic submenu per detected game, plus Open
dashboard / Start-Stop recording / Snapshot-copy / Quit. Reuses the dashboard's
sample stream; drives existing MainWindow flows.

- MainWindow creates the tray when one is available; closing the window hides to
  tray (Quit exits); setQuitOnLastWindowClosed(False) so dialogs don't quit it.
- app: `--tray` starts hidden for autostart.
- tests/test_gui_smoke.py: construct MainWindow headless + exercise the tray, so
  a startup crash (like the 0.18.0 import bug) fails the build. Skips if no PySide6.
- docs: M10/M11 marked done in MODULES/ROADMAP.

Completes the Desktop UI bundle (M10 + M11).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/MODULES.md

@@ -16,7 +16,7 @@ Status: ⬜ not started · 🟦 designing · 🟨 in progress · ✅ done
 | M5 | System inventory | Diagnostics | none (opt: lm-sensors, dmidecode) | all | P1 | ✅ |
 | M6 | Gaming env checks | Diagnostics | none | all | P2 | 🟨 |
 | M10 | Desktop GUI | Desktop UI | **python3-pyside6** | all | P2 | ✅ |
-| M11 | Tray / menu-bar applet | Desktop UI | **python3-pyside6** (+ AppIndicator on GNOME) | all | P2 | ⬜ |
+| M11 | Tray / menu-bar applet | Desktop UI | **python3-pyside6** (+ AppIndicator on GNOME) | all | P2 | ✅ |
 | M9 | Installer | (meta) | none | all | P1 | 🟨 |
 | M12 | Session sharing / remote assist | Sharing | none (Tier 3: tmate/sshx) | all | P3 | 🟨 |
 | M13 | Auto-update | (core) | none (stdlib; user-local file swap) | all | P3 | ✅ |
@@ -73,10 +73,14 @@ Status: ⬜ not started · 🟦 designing · 🟨 in progress · ✅ done
   nav, a live dashboard (circular gauges + collapsible per-subsystem cards, temperature-
   colored values), and a **Recording/Logs page** with full M3 controls (start/stop/status +
   post-crash report). Health/Inventory remain placeholders until M4/M5. GUI-first per D17.
-- **M11 Tray applet** — `QSystemTrayIcon` menu-bar applet. Dropdown shows live M1 readouts
-  (CPU temp, GPU temp, memory used/total, status dot) and is led by a **Run Diagnostic**
-  action (the guided diagnostic session), plus Open dashboard / Start-Stop recording /
-  Snapshot / Quit (D13). Optional; shares the Qt dependency with M10.
+- **M11 Tray applet** — `QSystemTrayIcon` menu-bar applet. *Implemented (`gui/tray.py`, D13):*
+  the menu shows live M1 readouts (CPU temp, GPU temp, memory used/total) + a status line
+  (Normal / Hot / GPU not responding), led by a **Run Diagnostic** submenu (per detected game →
+  the guided session), plus Open dashboard / Start-Stop recording / Snapshot-copy / Quit. It
+  shares the dashboard's sample stream (no extra sampling) and drives the existing MainWindow
+  flows. With a tray present, closing the window **hides to the tray** (Quit exits); `rigdoctor-gui
+  --tray` starts hidden for autostart. Optional; shares the Qt dependency with M10. *Needs a tray
+  host* — on GNOME that means the AppIndicator extension; degrades to no-op if none is available.
 - **M9 Installer** — interactive wizard layered on the `.deb` (D8); apt-first dependency
   resolution; enables the logger service and trigger mode. *Implemented (first cut):* distro/
   package-manager/GPU detection (`core/sysenv`), an optional-component catalog (`core/catalog`),

docs/ROADMAP.md

@@ -37,9 +37,11 @@ Ubuntu + NVIDIA first; `.deb` distribution (see `DECISIONS.md`).
 - [ ] SMART integration (smartmontools if present)
 
 ## Phase 4 — Desktop UI & installer
-- [ ] M10 desktop GUI (PySide6: dashboard, log browser, report viewer, logger controls)
-- [ ] M11 tray / menu-bar applet (QSystemTrayIcon: live M1 readouts + Run Diagnostic +
-      supporting actions — D13)
+- [x] M10 desktop GUI (PySide6: dashboard w/ history graphs, logs, health, games, environment,
+      inventory, setup, notifications, share)
+- [x] M11 tray / menu-bar applet (`gui/tray.py`: live CPU/GPU temp + memory readouts, status
+      line, Run Diagnostic submenu per game, Open dashboard / Start-Stop recording / Snapshot /
+      Quit — D13; close-to-tray, `--tray` autostart). Needs a tray host (AppIndicator on GNOME).
 - [~] Guided diagnostic session (pick game → focused M3 capture → M4 scan → findings),
       shared by tray/GUI/CLI — *core + CLI + GUI done* (`core/diagnostic.py`, `rigdoctor
       diagnose start/status/finish`, and a **Run Diagnostic** button per game on the GUI Games