feat: publish Mimir open core updates

[jb-thery]

Summary

• Prepare the next npm package release for @jcode.labs/mimir and @jcode.labs/mimir-tts as 0.4.11.
• Add core diagnostics for ingestion usefulness, empty-text files, unsupported-file recommendations, usage reporting, and retrieval evaluation surfaces.
• Keep release publication on the protected Publish npm workflow; this PR does not deploy the landing site or build native Tauri artifacts.

How to Test

• pnpm validate
• git diff --check