perf(db): add missing indexes, fix N+1 batch delete, add pagination limits

- Add indexes on Resource(blueprintId, roleId), DemandRequirement(roleId),
  Assignment(roleId) — commonly filtered FK columns that were missing indexes
- Replace N+1 batch delete pattern (2N queries) with findAllocationEntries()
  that does 2 total queries via findMany({ id: { in: ids } })
- Add take/skip pagination with default limit of 500 to listDemands and
  listAssignments to prevent unbounded result sets

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages/application/src/index.ts

@@ -50,6 +50,7 @@ export {
 
 export {
   findAllocationEntry,
+  findAllocationEntries,
   loadAllocationEntry,
   type AllocationEntryResolution,
 } from "./use-cases/allocation/load-allocation-entry.js";