v0.2.12

Release v0.2.12\n\nThis release supersedes v0.2.11 for launch use. v0.2.11 was published before the provider edit recovery fix.\n\nHighlights:\n- Fix provider edit/save being blocked by unrelated stale model provider_id errors.\n- Keep full config/model saves strict while allowing provider edits needed for recovery.\n- Improve Web provider save error visibility.\n- Include model metadata search API coverage.\n\nVerified:\n- go test -count=1 ./...\n- go vet ./...\n- go build ./cmd/server\n- node --check extracted Web script\n- build-test.sh build/start/test\n- temp-config PUT /admin/api/providers/usecpa returns 200 with unrelated stale model binding

Full Changelog: v0.2.11...v0.2.12