feat(schema): improve MCP and A2A modules

[akijakya]

Schema Extensions for MCP and A2A Modules

Improved structured searchability and discovery capabilities by moving essential metadata from generic annotations into schema-defined fields, while maintaining full fidelity storage of original data sources.

MCP Module

• Better alignment with the current MCP registry record schema
• Move critical MCP server data from annotations to structured schema fields
• Implement hybrid structure: common server fields (name, description, prompts, resources, tools) at module level with a unified connections array for all connection types
• Remove obsolete capabilities attribute
• Add mcp_data field to preserve full original MCP registry JSON
• Update transport types to align with official MCP schema (stdio, streamable-http, sse)

A2A Module

• Align a2a_capabilities with A2A proto specification (complex object structure)
• Remove transports field in favor of supported_interfaces
• Add structured discovery-critical fields (protocol_binding, provider info, supported_interfaces)

Closes #349
Closes #350

[github-actions]

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Build	Format	Lint	Breaking	Updated (UTC)
✅ passed	✅ passed	✅ passed	✅ passed	Dec 3, 2025, 9:18 AM