M31: verify RAG inventory and polish attention queue

docs/09-ragcore-integration.md

@@ -26,12 +26,17 @@ metadata.
 - `reported_synced_document_count`, `reported_failed_document_count` and `last_sync_at`: the latest persisted result reported by the central n8n synchronization workflow;
 - `document_count`: documents independently verified as indexed by the active provider.
 
-The current RAGcore contract deliberately has no corpus-size or space-browse endpoint. For
-the RAGcore provider, `document_count` therefore remains `null`; a successful upload report
-is never relabelled as proof that indexing and publishing completed. The deterministic demo
-provider can verify its in-memory corpus and reports `statistics_state=verified`. RAGcore
-reports `sync_reported` only when a persisted workflow callback exists, otherwise
-`not_reported`.
+The RAGcore contract deliberately has no corpus-size or space-browse endpoint. It does
+provide an exact identity lookup through `GET /v1/documents?source_id=...&external_id=...`.
+Fleet Ops uses that documented read contract concurrently and with bounded per-request
+timeouts for every managed source in the requested language. A document counts only when
+RAGcore returns exactly one active document in the configured space with a published active
+version whose `content_sha256` matches Fleet Ops's authoritative file. Results are cached
+for five minutes. This produces an independently verified `document_count` without changing
+RAGcore or relabelling an upload/sync report as index evidence. If exact verification is
+temporarily unavailable, `document_count` remains `null` and the sync report stays visibly
+separate. Both the deterministic provider and a successful exact RAGcore check report
+`statistics_state=verified`.
 
 ## Required adapter interface