feat: add mcp connections

Summary

Adds comprehensive MCP (Model Context Protocol) connection management with OAuth support, connection testing, and structured tool output rendering. Includes settings UI for managing connections, new API routes for connection lifecycle, and enhanced tool call rendering with provider-specific formatters.

Changes

API Routes (apps/web/app/api/)

• Add MCP connections endpoints for CRUD operations (mcp/connections/route.ts, mcp/connections/[id]/route.ts)
• Add connection testing endpoint (mcp/connections/[id]/test/route.ts)
• Add OAuth flow endpoints for initiation and callback (mcp/oauth/initiate/route.ts, mcp/oauth/callback/route.ts)
• Update chat and sessions routes for MCP integration

Database (apps/web/lib/db/)

• Add MCP connections schema and migrations (schema.ts, migrations/0029_swift_ultimo.sql)
• Add MCP connections database layer (mcp-connections.ts)
• Update migration metadata and journal

MCP Library (apps/web/lib/mcp/)

• Add authentication utilities (auth.ts)
• Add OAuth implementation (oauth.ts)
• Add MCP client wrapper (client.ts)
• Add URL validation and security checks (validate.ts)
• Add MCP provider catalog (catalog.ts)

UI Components (apps/web/app/settings/ and apps/web/components/)

• Add MCP connections management section in settings (settings/mcp-connections-section.tsx)
• Add MCP provider icons component (mcp-icons.tsx)
• Consolidate MCP picker into composer attach menu (composer-attach-menu.tsx)

Tool Call Renderers (apps/web/components/tool-call/renderers/mcp/)

• Add provider-specific renderers for Notion, Granola, and default implementations
• Add structured output parsing and formatting (shared.tsx)
• Add search result, table, and page output formatters (output-search.tsx, output-table.tsx, output-page.tsx)
• Add provider source icons (source-icons.tsx)
• Add main MCP renderer coordinator (index.tsx)

Workflow & Chat

• Update chat workflow for MCP tool resolution (app/workflows/chat.ts)
• Update chat content display for session integration (app/chats/[chatId]/session-chat-content.tsx)
• Update agent system prompt with tool labels (packages/agent/system-prompt.ts)

Dependencies

• Update package.json dependencies across monorepo packages
• Update lock files with new dependency versions

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