feat(updates): titlebar update indicator + dev injectors for the update flow

- light up the Phokus iris's focal point (pulsing amber) in the titlebar when
  an update is pending; click goes straight to install, with a fast custom
  tooltip (native title delay was too slow)
- PhokusMark gains an optional dotClassName to render the central focal point
- DemoPanel: inject every updater state (available/downloading/installing/
  error/up-to-date), which is otherwise unreachable without a remote latest.json

src/components/DemoPanel.tsx

@@ -1,10 +1,12 @@
-import { useEffect, useState } from "react";
+import { useEffect, useRef, useState } from "react";
 import { FolderJobProgress, useGalleryStore } from "../store";
 
 // Dev-only screenshot/demo helper. Injects frozen UI states that are otherwise
-// too transient to capture (e.g. the background-worker pipeline, which drains
-// in under a second on a fast machine). Gated by import.meta.env.DEV in App.tsx
-// so the whole thing is tree-shaken out of production builds.
+// too transient (or unreachable) to capture: the background-worker pipeline,
+// which drains in under a second, and the auto-updater flow, which never fires
+// locally because there's no remote latest.json to check against.
+// Gated by import.meta.env.DEV in App.tsx so the whole thing is tree-shaken out
+// of production builds.
 //
 // Toggle the controls with Ctrl+Shift+D. Injected state persists in the store
 // while the panel is hidden, so: open → inject → hide → screenshot.
@@ -36,9 +38,12 @@ const BUSY_PRESETS: Partial<FolderJobProgress>[] = [
   { embedding_ready: 40, tagging_ready: 18, tagging_pending: 22 },
 ];
 
+const DEMO_UPDATE_VERSION = "0.2.0";
+
 export function DemoPanel() {
   const folders = useGalleryStore((state) => state.folders);
   const [open, setOpen] = useState(false);
+  const downloadTimer = useRef<number | null>(null);
 
   useEffect(() => {
     const onKey = (event: KeyboardEvent) => {
@@ -51,6 +56,16 @@ export function DemoPanel() {
     return () => window.removeEventListener("keydown", onKey);
   }, []);
 
+  const stopTimer = () => {
+    if (downloadTimer.current !== null) {
+      window.clearInterval(downloadTimer.current);
+      downloadTimer.current = null;
+    }
+  };
+
+  // Stop any running download animation when the panel unmounts.
+  useEffect(() => stopTimer, []);
+
   const injectBusy = () => {
     const progress: Record<number, FolderJobProgress> = {};
     folders.slice(0, BUSY_PRESETS.length).forEach((folder, index) => {
@@ -71,36 +86,135 @@ export function DemoPanel() {
 
   const clear = () => useGalleryStore.setState({ mediaJobProgress: {} });
 
+  // --- Updater flow ---------------------------------------------------------
+  // These drive the real UpdateToast + Settings "About" row. The Install button
+  // stays inert (there's no real pendingUpdate), so this validates the
+  // presentation only — see DemoPanel's header note for the real e2e path.
+
+  const updateAvailable = () => {
+    stopTimer();
+    useGalleryStore.setState({
+      updateStatus: "available",
+      updateVersion: DEMO_UPDATE_VERSION,
+      updateProgress: null,
+      updateError: null,
+      updateDismissed: false,
+    });
+  };
+
+  // Indeterminate pulse, then climb 0 → 100%, then flip to "installing".
+  const simulateDownload = () => {
+    stopTimer();
+    useGalleryStore.setState({
+      updateStatus: "downloading",
+      updateVersion: DEMO_UPDATE_VERSION,
+      updateProgress: null,
+      updateError: null,
+      updateDismissed: false,
+    });
+    let progress = 0;
+    window.setTimeout(() => {
+      downloadTimer.current = window.setInterval(() => {
+        progress = Math.min(progress + 0.07, 1);
+        useGalleryStore.setState({ updateProgress: progress });
+        if (progress >= 1) {
+          stopTimer();
+          useGalleryStore.setState({ updateStatus: "installing" });
+        }
+      }, 200);
+    }, 700);
+  };
+
+  const updateInstalling = () => {
+    stopTimer();
+    useGalleryStore.setState({
+      updateStatus: "installing",
+      updateVersion: DEMO_UPDATE_VERSION,
+      updateProgress: 1,
+      updateDismissed: false,
+    });
+  };
+
+  const updateError = () => {
+    stopTimer();
+    useGalleryStore.setState({
+      updateStatus: "error",
+      updateError: "Could not reach the update server (connection timed out).",
+      updateDismissed: false,
+    });
+  };
+
+  const updateUpToDate = () => {
+    stopTimer();
+    useGalleryStore.setState({ updateStatus: "upToDate", updateVersion: null, updateError: null });
+  };
+
+  const resetUpdate = () => {
+    stopTimer();
+    useGalleryStore.setState({
+      updateStatus: "idle",
+      updateVersion: null,
+      updateProgress: null,
+      updateError: null,
+      updateDismissed: false,
+    });
+  };
+
   if (!open) return null;
 
+  const injectBtn =
+    "rounded-md border border-amber-400/30 bg-amber-500/15 px-2 py-1.5 text-left hover:bg-amber-500/25";
+  const neutralBtn =
+    "rounded-md border border-white/10 bg-white/[0.06] px-2 py-1.5 text-left text-gray-300 hover:bg-white/10";
+
   return (
-    <div className="fixed bottom-4 left-4 z-[100] w-56 rounded-lg border border-amber-400/40 bg-amber-950/90 p-3 text-xs text-amber-100 shadow-xl backdrop-blur">
+    <div className="fixed bottom-4 left-4 z-[100] max-h-[calc(100vh-2rem)] w-56 overflow-y-auto rounded-lg border border-amber-400/40 bg-amber-950/90 p-3 text-xs text-amber-100 shadow-xl backdrop-blur">
       <div className="mb-2 flex items-center justify-between">
         <span className="font-semibold uppercase tracking-wide">Demo · Ctrl+Shift+D</span>
       </div>
+
+      <p className="mb-1.5 text-[11px] font-semibold uppercase tracking-wide text-amber-200/60">Pipeline</p>
       <p className="mb-2 text-[11px] leading-snug text-amber-200/70">
         Inject a frozen worker-bar state, hide this panel, then screenshot.
       </p>
       <div className="flex flex-col gap-1.5">
-        <button
-          className="rounded-md border border-amber-400/30 bg-amber-500/15 px-2 py-1.5 text-left hover:bg-amber-500/25"
-          onClick={injectBusy}
-        >
+        <button className={injectBtn} onClick={injectBusy}>
           Pipeline: busy (3 folders)
         </button>
-        <button
-          className="rounded-md border border-amber-400/30 bg-amber-500/15 px-2 py-1.5 text-left hover:bg-amber-500/25"
-          onClick={injectSingleEmbedding}
-        >
+        <button className={injectBtn} onClick={injectSingleEmbedding}>
           Pipeline: embedding (1 folder)
         </button>
-        <button
-          className="rounded-md border border-white/10 bg-white/[0.06] px-2 py-1.5 text-left text-gray-300 hover:bg-white/10"
-          onClick={clear}
-        >
+        <button className={neutralBtn} onClick={clear}>
           Clear injected state
         </button>
       </div>
+
+      <div className="my-3 h-px bg-amber-400/20" />
+
+      <p className="mb-1.5 text-[11px] font-semibold uppercase tracking-wide text-amber-200/60">Update flow</p>
+      <p className="mb-2 text-[11px] leading-snug text-amber-200/70">
+        Drives the real toast (bottom-right) + Settings → About row. Install is inert here.
+      </p>
+      <div className="flex flex-col gap-1.5">
+        <button className={injectBtn} onClick={updateAvailable}>
+          Update available
+        </button>
+        <button className={injectBtn} onClick={simulateDownload}>
+          Simulate download → install
+        </button>
+        <button className={injectBtn} onClick={updateInstalling}>
+          Installing
+        </button>
+        <button className={injectBtn} onClick={updateError}>
+          Check failed (error)
+        </button>
+        <button className={injectBtn} onClick={updateUpToDate}>
+          Up to date
+        </button>
+        <button className={neutralBtn} onClick={resetUpdate}>
+          Reset updater state
+        </button>
+      </div>
     </div>
   );
 }