feat: keep Clipbin recording in the tray

Add native Linux SNI and Windows notification-area trays, single-instance reopening, background startup and login entries. Preserve recording and discovery after close, with clean Quit and reachable no-tray fallbacks.

Track capture-source audio delivery independently of silent output tracks and warn without stopping video. Give clip metadata its own row and shape labels at final bounds to avoid GPUI 0.2.2 truncation cache and text-run bugs.

Validated with strict workspace checks, 57 tests, Windows core/OBS/probe cross-clippy, all ten capture scenarios, tray/session/clips/playback rigs and narrow/wide screenshots. Document runtime validation gaps.

scripts/validate/linux-rig.sh

@@ -115,6 +115,19 @@ else
     result "${name}" 1
 fi
 
+# 9. Capture audio disappears while video/output remain healthy.
+name=audio-source-lost
+"${rig}" bash -c "'${probe}' record --seconds 15 --out '${out}/${name}' & p=\$!; sleep 6; kill \$(cat \"\${CLIPBIN_RIG_DIR}/pulse.pid\"); wait \$p" \
+    > "${out}/${name}.log" 2>&1
+probe_exit=$?
+if [[ "${probe_exit}" == 0 ]] && has "${out}/${name}.log" "status=Recording" \
+    && has "${out}/${name}.log" "audio capture lost" \
+    && ! has "${out}/${name}.log" "status=failed"; then
+    result "${name}" 0 "video continued; audio loss surfaced as degraded"
+else
+    result "${name}" 1
+fi
+
 echo
 if [[ "${failures}" == 0 ]]; then
     echo "All scenarios passed. Logs in ${out}"