feat(admin): track VS Code Marketplace installs in the dashboard

app/admin/page.tsx

@@ -59,6 +59,16 @@ type Summary = {
     }>;
     totals: { last_week: number; last_month: number };
   };
+  marketplace?: {
+    extensions: Array<{
+      extension: string;
+      installs: number;
+      downloads: number;
+      rating: number;
+      rating_count: number;
+    }>;
+    totals: { installs: number; downloads: number };
+  };
   generated_at: string;
 };
 
@@ -71,7 +81,12 @@ export default function AdminPage() {
   const [loading, setLoading] = useState(false);
 
   useEffect(() => {
+    // Read the saved admin token AFTER mount (not via a lazy useState
+    // initializer) so the server and initial client render match — reading
+    // localStorage during render would cause a hydration mismatch on the
+    // controlled password input below.
     const saved = window.localStorage.getItem(TOKEN_KEY);
+    // eslint-disable-next-line react-hooks/set-state-in-effect
     if (saved) setToken(saved);
   }, []);
 
@@ -166,6 +181,45 @@ export default function AdminPage() {
               </table>
             </section>
           )}
+          {data.marketplace && data.marketplace.extensions.length > 0 && (
+            <section>
+              <h2 className="text-lg font-semibold">VS Code Marketplace</h2>
+              <div className="mt-3 grid grid-cols-2 gap-3 sm:grid-cols-2">
+                <Stat
+                  label="Total installs"
+                  value={fmt(data.marketplace.totals.installs)}
+                />
+                <Stat
+                  label="Total downloads"
+                  value={fmt(data.marketplace.totals.downloads)}
+                />
+              </div>
+              <table className="mt-4 w-full text-sm">
+                <thead className="text-left text-xs uppercase text-slate-500">
+                  <tr>
+                    <th className="py-2">Extension</th>
+                    <th className="text-right">Installs</th>
+                    <th className="text-right">Downloads</th>
+                    <th className="text-right">Rating</th>
+                  </tr>
+                </thead>
+                <tbody>
+                  {data.marketplace.extensions.map((e) => (
+                    <tr key={e.extension} className="border-t border-slate-100">
+                      <td className="py-2 font-mono text-xs">{e.extension}</td>
+                      <td className="text-right">{fmt(e.installs)}</td>
+                      <td className="text-right">{fmt(e.downloads)}</td>
+                      <td className="text-right">
+                        {e.rating_count > 0
+                          ? `${e.rating.toFixed(1)}★ (${e.rating_count})`
+                          : "—"}
+                      </td>
+                    </tr>
+                  ))}
+                </tbody>
+              </table>
+            </section>
+          )}
           <section>
             <h2 className="text-lg font-semibold">Revenue (Polar)</h2>
             {polarError && (

app/api/admin/summary/route.ts

@@ -282,10 +282,68 @@ export async function GET(req: Request) {
     { last_week: 0, last_month: 0 }
   );
 
+  // VS Code Marketplace — the one distribution channel npm can't see. Public
+  // gallery API; resilient (any failure yields zeros, never breaks the page).
+  const VSCODE_EXTENSIONS = ["asafamos.axle-a11y"];
+  const marketplaceData = await Promise.all(
+    VSCODE_EXTENSIONS.map(async (ext) => {
+      try {
+        const res = await fetch(
+          "https://marketplace.visualstudio.com/_apis/public/gallery/extensionquery",
+          {
+            method: "POST",
+            cache: "no-store",
+            headers: {
+              "Content-Type": "application/json",
+              Accept: "application/json;api-version=3.0-preview.1",
+            },
+            body: JSON.stringify({
+              filters: [{ criteria: [{ filterType: 7, value: ext }] }],
+              flags: 914,
+            }),
+          }
+        );
+        const json = (await res.json()) as {
+          results?: Array<{
+            extensions?: Array<{
+              statistics?: Array<{ statisticName: string; value: number }>;
+            }>;
+          }>;
+        };
+        const stats = json?.results?.[0]?.extensions?.[0]?.statistics ?? [];
+        const stat = (name: string) =>
+          Number(stats.find((s) => s.statisticName === name)?.value ?? 0);
+        return {
+          extension: ext,
+          installs: stat("install"),
+          downloads: stat("downloadCount"),
+          rating: stat("averagerating"),
+          rating_count: stat("ratingcount"),
+        };
+      } catch {
+        return {
+          extension: ext,
+          installs: 0,
+          downloads: 0,
+          rating: 0,
+          rating_count: 0,
+        };
+      }
+    })
+  );
+  const marketplaceTotals = marketplaceData.reduce(
+    (acc, row) => ({
+      installs: acc.installs + row.installs,
+      downloads: acc.downloads + row.downloads,
+    }),
+    { installs: 0, downloads: 0 }
+  );
+
   return NextResponse.json({
     stats: kvData,
     polar: polarData,
     npm: { packages: npmData, totals: npmTotals },
+    marketplace: { extensions: marketplaceData, totals: marketplaceTotals },
     generated_at: new Date().toISOString(),
   });
 }