v0.4.6 — Contract validation and release alignment

What's changed

• Aligns public docs around v0.4.6 as the current stable release and keeps main / tag / GitHub Release in sync.
• Deepens scripts/check_mcp_drift.py to validate schema enums, tool annotations, local package contracts, and safe non-writing smoke tests.
• Keeps known backend schema gaps visible as non-fatal warnings until the live MCP server is deployed with the matching schema updates.
• Tracks the server-side schema follow-up in issue #13, with a matching draft PR open in ChuluuMGL/DY-Official-Site.

Validation

• python3 -m json.tool skill.json
• python3 -m py_compile scripts/check_mcp_drift.py
• python3 scripts/check_mcp_drift.py
• git diff --check
• GitHub Actions MCP Drift Check succeeded on main.