MCP: remove fake GridSmith server boundary

[fredporter]

Outcome

• removes the invalid repo-level MCP config that advertised uCore, Ollama, HiveMind, Feed, and GridSmith as equivalent MCP servers
• removes GridSmith's hand-rolled HTTP JSON-RPC server, binary, and generated outputs
• keeps GridSmith's package and CLI contracts intact for the uCore bridge
• removes the obsolete AI setup script and stale provider/MCP architecture guide
• establishes uCore udos-mcp as the only external MCP exposure owner
• aligns README, boundary, execution-plan, learning, and skills docs

Contraction

• 3,749 lines removed; 43 lines added

Verification

• monorepo build passed
• 188 JavaScript/TypeScript tests passed
• 193 Python runtime/shared tests passed; 48 environment-dependent skips
• lockfile, reference audit, and diff checks passed