feat(landing): add Atlas landing page with Astro static site

Implement the full landing page for atlas.atomstorm.ai per the PRD at
Docs/Execution/Landing-Page-PRD-2026-03-14.md. Includes design spec,
bilingual Astro site, CI pipeline, and all assets.

Key deliverables:
- DESIGN.md: 7-section Atom Web Design specification
- Astro 5.x static site with 15 components and 11 page sections
- Bilingual i18n (zh/en) with path-based routing
- Build-time GitHub release manifest integration
- Release channel state machine (Stable/Prerelease/Coming Soon)
- CSS design tokens mapped from AtlasBrand.swift
- Self-hosted fonts (Space Grotesk, Instrument Sans, IBM Plex Mono)
- OG social sharing images for both locales
- GitHub Actions workflow for GitHub Pages deployment
- Zero client JS, 227KB page weight, 17/17 quality checks passed

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Apps/LandingSite/scripts/fetch-release.ts

@@ -0,0 +1,142 @@
+/**
+ * Build-time script: Fetches latest release from GitHub API
+ * and writes release-manifest.json for the landing page.
+ *
+ * Usage: tsx scripts/fetch-release.ts
+ * Env: GITHUB_TOKEN (optional, increases rate limit)
+ */
+
+import { writeFileSync } from 'node:fs';
+import { join, dirname } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+const OWNER = 'nicekid1';
+const REPO = 'CleanMyPc';
+const OUTPUT = join(__dirname, '..', 'src', 'data', 'release-manifest.json');
+
+interface ReleaseManifest {
+  channel: 'stable' | 'prerelease' | 'none';
+  version: string | null;
+  publishedAt: string | null;
+  releaseUrl: string | null;
+  assets: {
+    dmg: string | null;
+    zip: string | null;
+    pkg: string | null;
+    sha256: string | null;
+  };
+  gatekeeperWarning: boolean;
+  installNote: string | null;
+  tagName: string | null;
+  generatedAt: string;
+}
+
+function findAsset(assets: any[], suffix: string): string | null {
+  const asset = assets.find((a: any) =>
+    a.name.toLowerCase().endsWith(suffix.toLowerCase())
+  );
+  return asset?.browser_download_url ?? null;
+}
+
+async function fetchRelease(): Promise<ReleaseManifest> {
+  const headers: Record<string, string> = {
+    Accept: 'application/vnd.github.v3+json',
+    'User-Agent': 'atlas-landing-build',
+  };
+
+  if (process.env.GITHUB_TOKEN) {
+    headers.Authorization = `Bearer ${process.env.GITHUB_TOKEN}`;
+  }
+
+  // Try latest release first, then fall back to all releases
+  let release: any = null;
+
+  try {
+    const latestRes = await fetch(
+      `https://api.github.com/repos/${OWNER}/${REPO}/releases/latest`,
+      { headers }
+    );
+
+    if (latestRes.ok) {
+      release = await latestRes.json();
+    }
+  } catch {
+    // Ignore — try all releases next
+  }
+
+  if (!release) {
+    try {
+      const allRes = await fetch(
+        `https://api.github.com/repos/${OWNER}/${REPO}/releases?per_page=5`,
+        { headers }
+      );
+
+      if (allRes.ok) {
+        const releases = await allRes.json();
+        if (Array.isArray(releases) && releases.length > 0) {
+          release = releases[0];
+        }
+      }
+    } catch {
+      // Will return "none" channel
+    }
+  }
+
+  if (!release) {
+    return {
+      channel: 'none',
+      version: null,
+      publishedAt: null,
+      releaseUrl: `https://github.com/${OWNER}/${REPO}`,
+      assets: { dmg: null, zip: null, pkg: null, sha256: null },
+      gatekeeperWarning: false,
+      installNote: null,
+      tagName: null,
+      generatedAt: new Date().toISOString(),
+    };
+  }
+
+  const isPrerelease = release.prerelease === true;
+  const version = (release.tag_name ?? '').replace(/^V/i, '') || null;
+  const assets = release.assets ?? [];
+
+  return {
+    channel: isPrerelease ? 'prerelease' : 'stable',
+    version,
+    publishedAt: release.published_at ?? null,
+    releaseUrl: release.html_url ?? `https://github.com/${OWNER}/${REPO}/releases`,
+    assets: {
+      dmg: findAsset(assets, '.dmg'),
+      zip: findAsset(assets, '.zip'),
+      pkg: findAsset(assets, '.pkg'),
+      sha256: findAsset(assets, '.sha256'),
+    },
+    gatekeeperWarning: isPrerelease,
+    installNote: isPrerelease
+      ? 'This build is development-signed. macOS Gatekeeper may require "Open Anyway" or a right-click "Open" flow.'
+      : null,
+    tagName: release.tag_name ?? null,
+    generatedAt: new Date().toISOString(),
+  };
+}
+
+async function main() {
+  console.log(`Fetching release data for ${OWNER}/${REPO}...`);
+
+  try {
+    const manifest = await fetchRelease();
+    writeFileSync(OUTPUT, JSON.stringify(manifest, null, 2) + '\n');
+    console.log(`Wrote ${OUTPUT}`);
+    console.log(`  channel: ${manifest.channel}`);
+    console.log(`  version: ${manifest.version ?? '(none)'}`);
+    console.log(`  gatekeeperWarning: ${manifest.gatekeeperWarning}`);
+  } catch (err) {
+    console.error('Failed to fetch release, using fallback:', err);
+    // The build will use release-fallback.json via the data loader
+    process.exit(0); // Don't fail the build
+  }
+}
+
+main();