fix(db): recover an interrupted build of the keyword projection document index on replay

Author: waleedlatif1

packages/db/migrations/0373_keyword_tin_document_index.sql

@@ -2,5 +2,7 @@
 -- document id; with no index on that column every ACL change scanned the whole projection.
 COMMIT;--> statement-breakpoint
 SET lock_timeout = 0;--> statement-breakpoint
+-- migration-safe: replay replaces only this new index to recover an interrupted concurrent build; existing indexes remain available.
+DROP INDEX CONCURRENTLY IF EXISTS "embedding_keyword_tin_document_idx";--> statement-breakpoint
 CREATE INDEX CONCURRENTLY IF NOT EXISTS "embedding_keyword_tin_document_idx" ON "embedding_keyword_tin" USING btree ("document_id");--> statement-breakpoint
 SET lock_timeout = '5s';