fix(gif): still previews + a11y for recent GIFs

Address findings from 2 review agents on the recent-GIFs row:

- Motion/perf: the Recent row rendered up to 16 full animated GIFs at
  once (autoplaying). Capture a small still image at pick time
  (fixed_width_small_still / *_still) into RecentGif.previewUrl and render
  that for the thumbnail, so recents no longer autoplay. Pre-existing
  recents without a preview fall back to the animated url. Re-send still
  uses the animated url, so the sent m.image is unchanged.

- a11y: the recent buttons all had the identical label "Send recent GIF".
  Give them positional labels ("Send recent GIF N of M") and wrap the grid
  in a role="group" labelled by the "Recent" section heading, so the row
  is a distinguishable, announced group.

Correctness review found no bugs (write-before-unmount, term gating,
dedupe, re-send fidelity all verified).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/components/GifPicker.tsx

@@ -19,10 +19,21 @@ type GifPickerInnerProps = {
 
 // Small monospace section header matching the picker's `// GIF_SEARCH` treatment
 // (lotusTerminal) / a muted label otherwise.
-function SectionLabel({ text, lotusTerminal }: { text: string; lotusTerminal: boolean }) {
+const RECENT_LABEL_ID = 'gif-picker-recent-label';
+
+function SectionLabel({
+  text,
+  lotusTerminal,
+  id,
+}: {
+  text: string;
+  lotusTerminal: boolean;
+  id?: string;
+}) {
   if (lotusTerminal) {
     return (
       <div
+        id={id}
         style={{
           padding: '4px 2px',
           fontFamily: "'JetBrains Mono', 'Cascadia Code', monospace",
@@ -39,6 +50,7 @@ function SectionLabel({ text, lotusTerminal }: { text: string; lotusTerminal: bo
   }
   return (
     <div
+      id={id}
       style={{
         padding: '2px 2px 4px',
         fontSize: '11px',
@@ -60,18 +72,22 @@ function RecentGifs({
 }: {
   recents: RecentGif[];
   lotusTerminal: boolean;
-  onPick: (url: string, width: number, height: number) => void;
+  onPick: (gif: RecentGif) => void;
 }) {
   return (
     <div style={{ marginBottom: 8 }}>
-      <SectionLabel text="Recent" lotusTerminal={lotusTerminal} />
-      <div style={{ display: 'grid', gridTemplateColumns: 'repeat(3, 1fr)', gap: 4 }}>
-        {recents.map((g) => (
+      <SectionLabel text="Recent" lotusTerminal={lotusTerminal} id={RECENT_LABEL_ID} />
+      <div
+        role="group"
+        aria-labelledby={RECENT_LABEL_ID}
+        style={{ display: 'grid', gridTemplateColumns: 'repeat(3, 1fr)', gap: 4 }}
+      >
+        {recents.map((g, i) => (
           <button
             key={g.url}
             type="button"
-            aria-label="Send recent GIF"
-            onClick={() => onPick(g.url, g.width, g.height)}
+            aria-label={`Send recent GIF ${i + 1} of ${recents.length}`}
+            onClick={() => onPick(g)}
             style={{
               padding: 0,
               border: 'none',
@@ -82,8 +98,10 @@ function RecentGifs({
               overflow: 'hidden',
             }}
           >
+            {/* A still preview (falls back to the animated url for pre-existing
+                recents) so the Recent row doesn't autoplay many GIFs at once. */}
             <img
-              src={g.url}
+              src={g.previewUrl ?? g.url}
               alt=""
               loading="lazy"
               style={{ width: '100%', height: '100%', objectFit: 'cover', display: 'block' }}
@@ -100,9 +118,9 @@ function GifPickerInner({ onSelect, requestClose, lotusTerminal }: GifPickerInne
   const [recents, setRecents] = useAtom(recentGifsAtom);
 
   const sendGif = useCallback(
-    (url: string, width: number, height: number) => {
-      setRecents((prev) => addRecentGif(prev, { url, width, height }));
-      onSelect(url, width, height);
+    (gif: RecentGif) => {
+      setRecents((prev) => addRecentGif(prev, gif));
+      onSelect(gif.url, gif.width, gif.height);
       requestClose();
     },
     [onSelect, requestClose, setRecents],
@@ -112,7 +130,16 @@ function GifPickerInner({ onSelect, requestClose, lotusTerminal }: GifPickerInne
     (gif: IGif, e: React.SyntheticEvent) => {
       e.preventDefault();
       const r = gif.images.downsized ?? gif.images.original;
-      sendGif(r.url, Number(r.width) || 200, Number(r.height) || 200);
+      const previewUrl =
+        gif.images.fixed_width_small_still?.url ??
+        gif.images.downsized_still?.url ??
+        gif.images.original_still?.url;
+      sendGif({
+        url: r.url,
+        width: Number(r.width) || 200,
+        height: Number(r.height) || 200,
+        previewUrl,
+      });
     },
     [sendGif],
   );

src/app/state/recentGifs.ts

@@ -5,6 +5,8 @@ export type RecentGif = {
   url: string;
   width: number;
   height: number;
+  /** A small still image used for the picker thumbnail (so recents don't all autoplay). */
+  previewUrl?: string;
 };
 
 const STORAGE_KEY = 'cinny_recent_gifs_v1';