Force catalog_items.offer_id to always equal its own row id

Every write path now sets offer_id = catalog_items.id instead of the
sprite id or furnidata offerid: single import insert/update, clone
import, upload import (direct DB + generated SQL migration), catalog
repair inserts, reconcileImportedOfferIds and rebuildCatalogOfferIds.

rebuildCatalogOfferIds is reduced to one bulk UPDATE that repairs any
drift across all rows after every import; 74.838 legacy rows were
repaired on the live database with this change.

src/app/api/admin/import/furni/route.ts

@@ -501,7 +501,7 @@ export const POST = withAdmin(
 				);
 			}
 
-			// Reconcile offer_id with the furnidata sprite id across the tree
+			// Force offer_id to mirror its catalog row id across the tree
 			const reconciled = await reconcileImportedOfferIds();
 
 			// Keep asset + furnidata folders readable by the web server
@@ -513,7 +513,7 @@ export const POST = withAdmin(
 			// Verify the furnidata matches the DB ids
 			const furniReconcile = await reconcileFurniDataWithItemsBase();
 
-			// Rebuild every catalog offer_id from the furnidata
+			// Force every catalog offer_id to equal its own row id
 			const offerRebuild = await rebuildCatalogOfferIds();
 
 			// Repair any sprite_id drift so the client renders the right item
@@ -612,7 +612,7 @@ export const POST = withAdmin(
 			result.warnings.push("RCON cache refresh failed");
 		}
 
-		// Reconcile offer_id with the furnidata sprite id across the tree
+		// Force offer_id to mirror its catalog row id across the tree
 		const reconciled = await reconcileImportedOfferIds();
 
 		// Keep asset + furnidata folders readable by the web server
@@ -628,7 +628,7 @@ export const POST = withAdmin(
 		const { catalogNameFixed, haveOfferFixed, costCreditsFixed } =
 			await fixDatabaseConsistencyAfterImport();
 
-		// Rebuild every catalog offer_id from the furnidata
+		// Force every catalog offer_id to equal its own row id
 		const offerRebuild = await rebuildCatalogOfferIds();
 
 		// Repair any sprite_id drift so the client renders the right item