* refactor: Restructure MCP registry system with caching
- Split MCPServersRegistry into modular components:
- MCPServerInspector: handles server inspection and health checks
- MCPServersInitializer: manages server initialization logic
- MCPServersRegistry: simplified registry coordination
- Add distributed caching layer:
- ServerConfigsCacheRedis: Redis-backed configuration cache
- ServerConfigsCacheInMemory: in-memory fallback cache
- RegistryStatusCache: distributed leader election state
- Add promise utilities (withTimeout) replacing Promise.race patterns
- Add comprehensive cache integration tests for all cache implementations
- Remove unused MCPManager.getAllToolFunctions method
* fix: Update OAuth flow to include user-specific headers
* chore: Update Jest configuration to ignore additional test files
- Added patterns to ignore files ending with .helper.ts and .helper.d.ts in testPathIgnorePatterns for cleaner test runs.
* fix: oauth headers in callback
* chore: Update Jest testPathIgnorePatterns to exclude helper files
- Modified testPathIgnorePatterns in package.json to ignore files ending with .helper.ts and .helper.d.ts for cleaner test execution.
* ci: update test mocks
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Co-authored-by: Danny Avila <danny@librechat.ai>
