feat: alerts (M8), notifications config page, and app icon (0.4.0)

- feat(alerts): desktop notifications (notify-send) for overheat (GPU/CPU past a
  configurable threshold), GPU-lost, and a new-version-available alert (once per
  version). Edge-triggered with cooldown so it doesn't spam (core/alerts.py)
- feat(gui): Notifications page to configure alerts (enable, GPU/CPU thresholds,
  Send test); changes apply live and persist via config.save_config/update_config
- feat(gui): ship a RigDoctor icon; the GUI self-registers the icon + .desktop on
  launch and sets the Wayland app-id, so the dock shows it after an update + relaunch
  (no installer re-run); installer/uninstaller updated to manage the icon
- config: alerts_enabled, gpu_temp_alert, cpu_temp_alert; flat-TOML writer
- tests for the alert monitor and config round-trip

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

install.sh

@@ -16,7 +16,8 @@ SCRIPT_DIR=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
 uninstall() {
     echo "Removing RigDoctor user-local install…"
     rm -rf "$VENV"
-    rm -f "$BIN_DIR/rigdoctor" "$BIN_DIR/rigdoctor-gui" "$DESKTOP_FILE"
+    rm -f "$BIN_DIR/rigdoctor" "$BIN_DIR/rigdoctor-gui" "$DESKTOP_FILE" \
+          "$DATA_HOME/icons/hicolor/scalable/apps/rigdoctor.svg"
     echo "Done. (Config and logs under ~/.config/rigdoctor and ~/.local/share/rigdoctor were kept.)"
 }
 
@@ -81,6 +82,17 @@ mkdir -p "$BIN_DIR"
 ln -sf "$VENV/bin/rigdoctor" "$BIN_DIR/rigdoctor"
 ln -sf "$VENV/bin/rigdoctor-gui" "$BIN_DIR/rigdoctor-gui"
 
+# Install the app icon (for the dock/launcher); fall back to a stock icon.
+ICON_NAME=utilities-system-monitor
+ICON_SRC=$("$VENV/bin/python" -c "import os, rigdoctor.gui as g; print(os.path.join(os.path.dirname(g.__file__), 'assets', 'rigdoctor.svg'))" 2>/dev/null || true)
+if [ -n "$ICON_SRC" ] && [ -f "$ICON_SRC" ]; then
+    ICON_DST="$DATA_HOME/icons/hicolor/scalable/apps/rigdoctor.svg"
+    mkdir -p "$(dirname "$ICON_DST")"
+    cp "$ICON_SRC" "$ICON_DST"
+    ICON_NAME=rigdoctor
+    command -v gtk-update-icon-cache >/dev/null 2>&1 && gtk-update-icon-cache -qtf "$DATA_HOME/icons/hicolor" 2>/dev/null || true
+fi
+
 mkdir -p "$DESKTOP_DIR"
 cat > "$DESKTOP_FILE" <<EOF
 [Desktop Entry]
@@ -88,10 +100,12 @@ Type=Application
 Name=RigDoctor
 Comment=Hardware monitoring & crash diagnostics for Linux gamers
 Exec=$VENV/bin/rigdoctor-gui
-Icon=utilities-system-monitor
+Icon=$ICON_NAME
 Terminal=false
 Categories=System;Monitor;Utility;
+StartupWMClass=rigdoctor
 EOF
+command -v update-desktop-database >/dev/null 2>&1 && update-desktop-database "$DESKTOP_DIR" 2>/dev/null || true
 
 echo
 echo "RigDoctor $("$VENV/bin/rigdoctor" --version 2>/dev/null | awk '{print $2}') installed."