v3.5.3

### Security

- **Vulnerabilities:** Fully remediated 12 High-Severity CodeQL vulnerabilities by migrating from Math.random to `crypto.randomUUID()`, wrapping SSE injection points with aggressive backslash escaping, sanitizing trailing HTTP fragments, and enforcing rigid SSRF HTTP verification schemes across internal routes.
- **Dependencies:** Upgraded Next.js to `^16.2.2` and Vite to `>=8.0.5` resolving critical DoS, arbitrary file reads and CSRF vectors in the build/server environments.

### Fixed

- **E2E Stability:** Eliminated extreme CI unreliability and transient test timeouts (Playwright) by propagating internal standalone `_next/static` assets properly and refactoring deep UI interactions inside defensive `expect().toPass()` loops.
- **Middleware:** Resolved infinite redirect loop on dashboard for fresh instances when requireLogin is disabled.
- **Core Fallbacks:** Preserved primary failure contexts and enhanced Edge-case error handling pipelines across chat and fallback loops.
- **Proxy/Hooks:** Optimized local git hooks, normalized token coverage endpoints into `/coverage`, and guarded GLM region lookups.

### 🛠️ Maintenance

- **CI/CD Stabilization:** Prevented random GitHub Runner freezes by decoupling sharded processes, adjusting test concurrencies, unref-ing active connections on server teardown, and strictly capping job timeout durations.

### Documentation

- **I18n Engine:** Synchronized and pushed deep Machine Translation updates across all 32 natively-supported languages (682 translation nodes aligned).

### Coverage

- **Testing:** Consolidated the workspace test coverage framework hitting 92.1% statement line coverage, with new rigid unit-tests matching API key policies and tool scopes.