feat(llm): add tool schema projections

[nexxeln]

Summary

• add named tool schema projections for OpenAI, Gemini, and Moonshot/Kimi compatibility
• apply model compatibility tool-schema projection before each protocol lowers tool schemas
• keep Gemini's protocol-wide projection intact while making it reusable for compatibility metadata

Tests

• cd packages/llm && bun typecheck
• cd packages/llm && bun test
• pre-push hook passed: bun turbo typecheck (29/29 tasks)