Wire best-effort Meilisearch index sync into the admin write paths
(create/update/delete/set_fields/set_visibility). Adds
SearchClient::sync_object (reindex if the object exists, remove if gone —
one uniform path), an optional AppState.search client, and a reindex
helper that logs failures via tracing without failing the committed
write. Server gains MEILI_URL/MEILI_MASTER_KEY/MEILI_INDEX config;
search stays disabled (no-op) when unset. reindex_all remains the
recovery path.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Implements build_document in the search crate: resolves Term and Authority
flexible-field values to their human-readable labels so reindex_all produces
documents that Meilisearch can match on label text, not raw UUIDs.
Adds integration test covering the full reindex→search round-trip.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>