refactor: remove all MCP code from codebase (#359)

* refactor: remove all MCP (Model Context Protocol) code

MCP UI was already removed in the latest main revamp. This cleans up
all remaining MCP backend code, endpoints, CLI commands, SDK
integrations, types, tests, and documentation across the entire
codebase.

Removed:
- control-plane/internal/mcp/ (manager, discovery, protocol client, etc.)
- control-plane/internal/cli/mcp.go + mcp/ stubs (CLI commands)
- control-plane/internal/handlers/ui/mcp.go (HTTP handlers)
- control-plane/internal/core/domain/mcp_health.go (domain models)
- MCP routes from server.go (/mcp/health, /mcp/status, etc.)
- MCP methods from AgentClient interface + HTTP implementation
- MCPStatusInfo from types, AgentStatus, heartbeat processing
- MCP health tracking from HealthMonitor and StatusManager
- MCP event types from node events
- sdk/python: mcp_manager, mcp_client, mcp_stdio_bridge, agent_mcp,
  dynamic_skills, and all MCP test files
- sdk/typescript: src/mcp/, types/mcp.ts, and MCP test files
- web/client: src/mcp/, components/mcp/, mcpUtils.ts, and all MCP
  references in pages/components/hooks/types
- MCP knowledgebase article, config models, benchmark references

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* chore: ignore hypothesis test cache

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix(ci): remove unused imports left over from MCP removal

- Remove unused `AgentNodeDetailsForUI` import in api.ts (TS6196)
- Remove unused `asdict` import in test_types.py (F401)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

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Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: AbirAbbas