Mount Precise public closing footer with hosted, versioned modules

[sarthakagrawal927]

Summary

• Mount the selected Precise C closing frame on the Astro homepage and shared Next app footer while preserving the existing app feedback control, /proof link, routes, and operating flows.
• Allow only the approved first-party footer sources in CSP: sassmaker.com and health.sassmaker.com in script-src, and sassmaker.com in font-src. Existing directives and headers remain unchanged.
• Load the existing versioned project-strip and AI-footer modules with data-host-only="true".

Validation

• pnpm quality — 88 test files, 515 tests, typecheck, docs and code-health gates pass.
• pnpm cf:build — Next Webpack, route verification, OpenNext, Astro build, and landing overlay pass.
• GitHub Actions CI run 37231148537 passes at 0b62c98fc3dfe7fb56f877a82155425aa40a01cf.
• Owner explicitly waived the rendered browser review. The receipt records visual and landing-to-app review as UNVERIFIED; no screenshots or completed visual checks are claimed.