chore: v2.8.7 — Git SSH keys in tabs, safer Artifacts preview and search

- Settings → Git → Your git identity: SSH keys are one tab per host kind
  (GitHub · GitLab, AWS CodeCommit, More keys, Other hosts); opens on the
  AWS tab when only an RSA key exists.
- Artifacts: a file type the sandboxed preview cannot show (Office, zip,
  PDF) offers Download only, never a blank Preview.
- Artifacts search: `%`/`_`/`\` in a query match literally (LIKE ... ESCAPE).
- Skill frontmatter rewrite replaces a key with its continuation lines and
  quotes values YAML could misread.
- Plugin marketplace.json is read with a 1 MB streaming cap.
- Artifact lists look each owner up once.

client/src/pages/Artifacts.tsx

@@ -13,6 +13,9 @@
  * the server's sandboxed `raw` route in a sandboxed iframe, so nothing a
  * shared HTML file carries runs on the dashboard's origin. Right-clicking a
  * card offers the same actions as its buttons, plus copying a page's link.
+ * Preview is offered only for what a browser shows inside that sandbox (text,
+ * images, HTML, audio/video); an Office file, a zip or a PDF is downloaded —
+ * the sandbox blocks both a download and the PDF viewer, so it would be blank.
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
  */
 
@@ -63,6 +66,9 @@ function fmtBytes(n: number | null): string {
 }
 
 const IMAGE = /\.(png|jpe?g|gif|webp|svg)$/i;
+// What the sandboxed preview can show: the server's typed list minus PDF.
+const PREVIEWABLE =
+  /\.(html?|md|markdown|txt|log|csv|tsv|json|ya?ml|sh|py|js|ts|png|jpe?g|gif|webp|svg|mp4|webm|mp3|wav)$/i;
 
 export function Artifacts() {
   const { t } = useTranslation("artifacts");
@@ -73,6 +79,7 @@ export function Artifacts() {
   const [items, setItems] = useState<Artifact[] | null>(null);
   const [adding, setAdding] = useState<ArtifactKind | null>(null);
   const [addMenu, setAddMenu] = useState(false);
+  const addMenuRef = useRef<HTMLDivElement>(null);
   const [preview, setPreview] = useState<{ item: Artifact; path: string } | null>(null);
 
   useEffect(() => {
@@ -105,6 +112,23 @@ export function Artifacts() {
     [load]
   );
 
+  // The Add menu closes on Escape or a click anywhere outside it.
+  useEffect(() => {
+    if (!addMenu) return;
+    const onDown = (e: MouseEvent) => {
+      if (!addMenuRef.current?.contains(e.target as Node)) setAddMenu(false);
+    };
+    const onKey = (e: KeyboardEvent) => {
+      if (e.key === "Escape") setAddMenu(false);
+    };
+    document.addEventListener("mousedown", onDown);
+    document.addEventListener("keydown", onKey);
+    return () => {
+      document.removeEventListener("mousedown", onDown);
+      document.removeEventListener("keydown", onKey);
+    };
+  }, [addMenu]);
+
   const server = !!settings?.serverMode;
 
   const share = async (a: Artifact) => {
@@ -186,11 +210,13 @@ export function Artifacts() {
           <p className="text-sm text-fg-muted">{t(server ? "subtitleServer" : "subtitle")}</p>
         </div>
         <div className="flex items-center gap-3">
-          <div className="relative">
+          <div className="relative" ref={addMenuRef}>
             <button
               type="button"
               className="btn-primary flex items-center gap-1.5 text-sm"
               data-testid="artifacts-add"
+              aria-haspopup="menu"
+              aria-expanded={addMenu}
               onClick={() => setAddMenu((v) => !v)}
             >
               <Plus className="h-4 w-4" />
@@ -334,7 +360,9 @@ function ArtifactCard({
     fn();
   };
   const previewPath = a.kind === "skill" ? "SKILL.md" : (a.files[0]?.path ?? "");
-  const canPreview = (a.kind === "file" || a.kind === "skill") && a.files.length > 0;
+  const canPreview =
+    a.files.length > 0 &&
+    (a.kind === "skill" || (a.kind === "file" && PREVIEWABLE.test(previewPath)));
   const btn =
     "flex items-center gap-1 rounded px-1.5 py-0.5 text-[11px] text-fg-secondary hover:bg-surface-3 hover:text-fg-primary";
   return (
@@ -598,6 +626,7 @@ function PreviewDialog({
   path: string;
   onClose: () => void;
 }) {
+  const { t } = useTranslation("artifacts");
   const [current, setCurrent] = useState(path);
   const url = api.artifacts.rawUrl(item.id, current);
   return (
@@ -624,7 +653,18 @@ function PreviewDialog({
           </ul>
         )}
         <div className="min-w-0 flex-1 rounded border border-border bg-white">
-          {IMAGE.test(current) && !/\.svg$/i.test(current) ? (
+          {!PREVIEWABLE.test(current) ? (
+            <div className="flex h-full flex-col items-center justify-center gap-3 bg-surface-1 p-6 text-center">
+              <p className="text-sm text-fg-secondary">{t("noPreview")}</p>
+              <a
+                href={api.artifacts.rawUrl(item.id, current, true)}
+                className="btn-primary flex items-center gap-1.5 text-sm"
+              >
+                <Download className="h-4 w-4" />
+                {t("download")}
+              </a>
+            </div>
+          ) : IMAGE.test(current) && !/\.svg$/i.test(current) ? (
             <img src={url} alt={current} className="h-full w-full object-contain" />
           ) : (
             // No allow-* tokens: a shared page renders, nothing in it runs.