feat: add You.com MCP server integration

[mouse-value-add]

Add You.com MCP Server Integration

What Changed

This PR adds You.com as a predefined MCP (Model Context Protocol) server option in deco Studio, enabling agents to access web search, content extraction, and research capabilities through You.com's MCP endpoint.

Key Features

• Predefined Server Integration: You.com appears as a recognized server option when users enter https://api.you.com/mcp
• Flexible Authentication: Supports both authenticated (API key) and keyless operation
• Multiple Connection Types: Works with SSE, HTTP, and WebSocket connection types
• User-Friendly Setup: Automatic provider hint detection with clear guidance
• Keyless Fallback: 100 free searches per day without requiring API key setup

Implementation Details

• Added youcom to the ConnectionProviderHint type system
• Implemented URL pattern matching for https://api.you.com/mcp
• Added comprehensive provider hints with token field customization
• Included test coverage for all connection scenarios
• Added documentation for setup and usage patterns

How to Test

1. Create New Connection:

   • Go to Connections → Create Connection
   • Select "SSE" as connection type
   • Enter URL: https://api.you.com/mcp
   • Notice automatic detection of You.com provider

2. Verify Provider Hints:

   • Observe custom token field label: "You.com API Key (optional)"
   • Check helper text about keyless operation
   • Confirm placeholder text shows example format

3. Test Authentication Options:

   • With API Key: Enter valid You.com API key in token field
   • Keyless: Leave token field empty for keyless operation

Agent Tools Available

Once connected, agents gain access to:

• you-search: Web search with customizable parameters
• you-contents: URL content extraction
• you-research: Synthesized research with citations

Migration Notes

This is a pure additive change with no breaking changes:

• Existing connections and configurations remain unchanged
• No database migrations required
• Backwards compatible with all existing provider hints

Validation Performed

✅ Provider hint detection works correctly for You.com URLs
✅ Supports all relevant connection types (SSE, HTTP, WebSocket)
✅ URL normalization handles trailing slashes properly
✅ Does not interfere with existing provider detection (GitHub, Perplexity)
✅ Test coverage added for all integration scenarios
✅ Documentation provides clear setup and usage guidance

Links

• You.com API Documentation: https://docs.you.com
• Get API Key: https://you.com/platform/api-keys
• Integration Documentation: docs/youcom-mcp-integration.md

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This integration makes You.com's web search and research capabilities immediately available to deco Studio users through the standard MCP protocol, with both authenticated and keyless operation modes supported.

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Summary by cubic

Adds You.com as a predefined MCP server in deco Studio so agents can use web search, content extraction, and research via https://api.you.com/mcp. Supports optional API key and keyless mode (100 free searches/day).

• New Features
  • Detects You.com provider when connecting to https://api.you.com/mcp over SSE, HTTP, or WebSocket.
  • Custom token field: "You.com API Key (optional)" with helper text for keyless use.
  • URL normalization handles trailing slashes and doesn’t affect existing providers.
  • Docs and tests added for setup and provider hint detection.

^{Written for commit c84a0e6. Summary will update on new commits.}