chore: stabilize universal refiner local updates

[OgeonX-Ai]

Summary

• rename the active universal-refiner package/bin and package runtime smoke to universal-refiner
• move repo config to .universal-refiner.json with legacy .gemini-refiner.json fallback
• add local Gemma/Ollama example config and docs
• harden snippet indexing against transient filesystem/canonicalization errors
• preserve Antigravity's incomplete dashboard/auto-heal/integration work in local stashes instead of shipping broken code

Verification

• npm.cmd run release:verify
• 48 test files passed, 283 tests passed
• 100% statements/branches/functions/lines coverage
• acceptance, tracked-turn, stress, abrupt recovery, soak, audit, secret scan, npm pack, and package-runtime smoke all passed