🔄 refactor: MCP Registry System with Distributed Caching (#10191)

* 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

---------

Co-authored-by: Danny Avila <danny@librechat.ai>

api/server/controllers/UserController.js

@@ -28,6 +28,7 @@ const { getMCPManager, getFlowStateManager } = require('~/config');
 const { getAppConfig } = require('~/server/services/Config');
 const { deleteToolCalls } = require('~/models/ToolCall');
 const { getLogStores } = require('~/cache');
+const { mcpServersRegistry } = require('@librechat/api');
 
 const getUserController = async (req, res) => {
   const appConfig = await getAppConfig({ role: req.user?.role });
@@ -198,7 +199,7 @@ const updateUserPluginsController = async (req, res) => {
       // If auth was updated successfully, disconnect MCP sessions as they might use these credentials
       if (pluginKey.startsWith(Constants.mcp_prefix)) {
         try {
-          const mcpManager = getMCPManager(user.id);
+          const mcpManager = getMCPManager();
           if (mcpManager) {
             // Extract server name from pluginKey (format: "mcp_<serverName>")
             const serverName = pluginKey.replace(Constants.mcp_prefix, '');
@@ -295,10 +296,11 @@ const maybeUninstallOAuthMCP = async (userId, pluginKey, appConfig) => {
   }
 
   const serverName = pluginKey.replace(Constants.mcp_prefix, '');
-  const mcpManager = getMCPManager(userId);
-  const serverConfig = mcpManager.getRawConfig(serverName) ?? appConfig?.mcpServers?.[serverName];
-
-  if (!mcpManager.getOAuthServers().has(serverName)) {
+  const serverConfig =
+    (await mcpServersRegistry.getServerConfig(serverName, userId)) ??
+    appConfig?.mcpServers?.[serverName];
+  const oauthServers = await mcpServersRegistry.getOAuthServers();
+  if (!oauthServers.has(serverName)) {
     // this server does not use OAuth, so nothing to do here as well
     return;
   }

api/server/controllers/mcp.js

@@ -10,6 +10,7 @@ const {
   getAppConfig,
 } = require('~/server/services/Config');
 const { getMCPManager } = require('~/config');
+const { mcpServersRegistry } = require('@librechat/api');
 
 /**
  * Get all MCP tools available to the user
@@ -65,7 +66,7 @@ const getMCPTools = async (req, res) => {
 
         // Get server config once
         const serverConfig = appConfig.mcpConfig[serverName];
-        const rawServerConfig = mcpManager.getRawConfig(serverName);
+        const rawServerConfig = await mcpServersRegistry.getServerConfig(serverName, userId);
 
         // Initialize server object with all server-level data
         const server = {