## Problem Follow-up to: #3586294 Parent: #3586310 `AiContextSelector::getPrefilteredPublishedItemIds()` returns NULL when `$scopeSubscriptions` is empty, so the chunk loop loads **every published context item** (full entities including content fields) on every AI request. This hits the very common "global items only" agent configuration. With thousands of items that's dozens of chunked queries, thousands of entity hydrations, and thousands of per-item plugin `matchesCurrentContext()` calls per request — the `match_all` broad-scan warning only logs, it doesn't avoid the work. ## Resolution For `SELECTION_MODE_MINIMAL` with no subscriptions, replace the full catalog scan with a targeted prefilter. Only candidates that can contribute in this mode are loaded: 1. **Global items** — from the scope index. 2. **Unindexed items** — published items with no scope index rows (includes target-entity-only items and unscoped items). Resolved via a LEFT JOIN anti-join on the entity data table. 3. **Current target-entity items** — explicit DER matches for the active entity context (covers items with both indexed subscription scope and a target entity reference). 4. **Custom non-subscription scope items** — items indexed under enabled scope plugins where `supportsSubscriptions()` is FALSE. `SELECTION_MODE_MATCH_ALL` with no subscriptions continues to use the full catalog scan. Implemented in [!210](https://git.drupalcode.org/project/ai_context/-/merge_requests/210). ## AI usage - [x] AI assisted issue