Align current pre-release documentation and specifications

[fredporter]

Summary

• replace false BASIC 1.0 release/runtime claims with concise pre-release ownership guidance
• remove obsolete Hivemind provider configuration and current development plan
• align integration, boundary, Skills Framework, tutorials, and course registry with RCP and uCore MCP ownership
• archive eight historical Sonic, DevStudio, v2.1, and GridSmith planning documents
• remove two exact duplicate gameplay planning copies
• leave only correct uCore udos-mcp references in current documentation

Verification

• course registry JSON validates
• clean workspace build passes
• 188 Node tests pass
• 198 Python tests pass, with 33 existing skips and 2 existing warnings
• current-doc MCP audit contains only canonical uCore gateway ownership statements