fix(landing,docs): use build-time GitHub star count, drop per-page api.github.com fetch (#560)

Removes the client-side api.github.com fetch from the landing navbar and the docs theme; both now render a build-time star count (docs via a new VitePress data loader). deploy-docs.yml gets GITHUB_TOKEN plus a daily refresh cron, mirroring deploy-landing.yml. Fixes #555.

apps/docs/.vitepress/theme/github-stars.data.ts

@@ -0,0 +1,57 @@
+// Build-time GitHub star count for the docs navbar. Fetched in Node during the
+// VitePress build (never from the browser), so the docs site makes no per-page
+// request to api.github.com. Mirrors the landing site's build-time getStarCount
+// (apps/landing/src/lib/stats.ts): sends an Authorization header when
+// GITHUB_TOKEN is set (CI) to lift the 60 req/hr unauthenticated limit, and
+// degrades to a maintained constant if the API is unreachable or rate-limited,
+// so a build never ships an empty count.
+import { defineLoader } from "vitepress";
+
+const GITHUB_REPO = "snapotter-hq/SnapOtter";
+
+// Fallback used when the upstream fetch fails. Keep roughly current so a
+// degraded build still shows a believable figure (matches STAR_FALLBACK in
+// apps/landing/src/lib/stats.ts).
+const STAR_FALLBACK = 1720;
+
+export interface GitHubStarsData {
+  /** Compact star count for display, e.g. "1.7k". */
+  display: string;
+}
+
+declare const data: GitHubStarsData;
+
+export { data };
+
+/** Compact integer formatting: 1720 -> "1.7k", 2_300_000 -> "2.3M". */
+function formatCompact(n: number): string {
+  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(1).replace(/\.0$/, "")}M`;
+  if (n >= 1_000) return `${(n / 1_000).toFixed(1).replace(/\.0$/, "")}k`;
+  return n.toString();
+}
+
+async function fetchStarCount(): Promise<number> {
+  try {
+    const token = process.env.GITHUB_TOKEN;
+    const res = await fetch(`https://api.github.com/repos/${GITHUB_REPO}`, {
+      headers: {
+        Accept: "application/vnd.github+json",
+        "User-Agent": "SnapOtter-Docs",
+        ...(token ? { Authorization: `Bearer ${token}` } : {}),
+      },
+    });
+    if (res.ok) {
+      const json = await res.json();
+      if (typeof json.stargazers_count === "number") return json.stargazers_count;
+    }
+  } catch {
+    // Network/JSON failure: fall through to the fallback below.
+  }
+  return STAR_FALLBACK;
+}
+
+export default defineLoader({
+  async load(): Promise<GitHubStarsData> {
+    return { display: formatCompact(await fetchStarCount()) };
+  },
+});