docs: add background job isolation policy to tenant isolation spec

Documents policy for all 5 existing background jobs:
- Knowledge Flywheel and PSA Retry flagged for account_id threading
- Chat Retention already follows correct pattern (model for others)
- Maintenance Schedule Firing needs account_id in queries + Session creation
- AI Conversation Expiry approved as cross-tenant with justification

Adds approved cross-tenant query registry and Phase 2 checklist items.

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

docs/superpowers/specs/2026-04-09-tenant-data-isolation-design.md

@@ -506,7 +506,84 @@ Gate: All RLS tests green after each batch. All integration tests green. Staging
 
 ---
 
-## Section 8: Open Questions
+## Section 8: Background Job Policy
+
+Background jobs and scheduled tasks that process tenant data are a distinct isolation surface. Unlike request-scoped endpoints, they do not have a `current_user` and must manage tenant context explicitly.
+
+### Policy
+
+Every background job that touches tenant tables must comply with one of two patterns:
+
+**Pattern A — `resolutionflow_admin` with explicit per-query `account_id` filtering**
+
+Use when: the job is inherently cross-tenant (e.g., processes all pending work across all accounts in a single pass). The admin role bypasses RLS, so explicit `account_id` filters in every query are mandatory — RLS is not the safety net here.
+
+```python
+# Allowed: cross-tenant batch SELECT for IDs only, then loop per-account
+result = await db.execute(
+    select(Model.id, Model.account_id).where(Model.status == "pending")
+)
+for row in result.all():
+    await _process_one(row.id, row.account_id, db)  # account_id threaded through
+
+# In the processing function: all queries must filter by account_id
+async def _process_one(record_id, account_id, db):
+    result = await db.execute(
+        select(Model).where(Model.id == record_id, Model.account_id == account_id)
+    )
+```
+
+**Pattern B — `resolutionflow_app` with `SET LOCAL` per tenant loop iteration**
+
+Use when: the job processes tenants one at a time and it is practical to set the tenant context per iteration.
+
+```python
+for account_id in account_ids:
+    async with async_session_maker() as db:
+        await db.execute(
+            text("SET LOCAL app.current_account_id = :id"),
+            {"id": str(account_id)}
+        )
+        # All queries in this block are RLS-enforced to this tenant
+```
+
+### No cross-tenant queries without justification
+
+No background job may issue a SELECT, UPDATE, or DELETE that spans multiple tenants' data in a single query without explicit written justification in the code comment and in this spec. Approved cross-tenant operations are documented below.
+
+### Inventory: Current Background Jobs
+
+| Job | File | Pattern | Status | Notes |
+|---|---|---|---|---|
+| Knowledge Flywheel | `knowledge_flywheel_scheduler.py` | Admin + explicit filter | **Needs update** | Batch SELECT across all accounts with no `account_id` filter. Must thread `account_id` from the session into all processing calls. |
+| PSA Retry | `psa_retry_scheduler.py` | Admin + explicit filter | **Needs update** | Batch SELECT across all accounts with no `account_id` filter. Must add `account_id` to batch query and thread through to `retry_failed_push`. |
+| Chat Retention Cleanup | `retention_cleanup.py` | Admin + explicit filter | **Correct pattern** | Already loops per-account with explicit `account_id` in all queries. Model for other jobs. Needs role update to `resolutionflow_admin`. |
+| Maintenance Schedule Firing | `scheduler.py` (`_fire_maintenance_schedule`) | Admin + explicit filter | **Needs update** | Fetches `MaintenanceSchedule` and `Tree` by ID without `account_id` filter. After Phase 1, `Session` creation must set `account_id`. Add `account_id` to all queries. |
+| AI Conversation Expiry | `scheduler.py` (`_cleanup_expired_ai_conversations`) | Admin, cross-tenant approved | **Correct pattern** | Cross-tenant DELETE by `expires_at` is explicitly justified: rows are expired regardless of tenant. Needs role update to `resolutionflow_admin`. Document this approval in code comment. |
+
+### Approved cross-tenant queries
+
+The following cross-tenant operations are explicitly approved. All others require a new entry here before shipping:
+
+| Job | Query | Justification |
+|---|---|---|
+| AI Conversation Expiry | `DELETE FROM ai_conversations WHERE expires_at < NOW()` | Time-based expiry is tenant-independent. Deleting expired rows does not expose data across tenants. |
+| Chat Retention Cleanup | `SELECT id FROM accounts` | Required to iterate per-account. Read of account IDs only; no tenant data accessed. |
+| Knowledge Flywheel (after fix) | `SELECT id, account_id FROM ai_sessions WHERE analysis_status='pending'` | Cross-tenant ID harvest only. No tenant data in the SELECT. `account_id` is threaded into per-tenant processing. |
+| PSA Retry (after fix) | `SELECT id, account_id FROM psa_post_logs WHERE status='pending_retry'` | Cross-tenant ID harvest only. `account_id` threaded into per-tenant processing. |
+
+### Checklist additions (Phase 2)
+
+- [ ] All background jobs updated to use `resolutionflow_admin` role via `DATABASE_ADMIN_URL`
+- [ ] Knowledge Flywheel: `account_id` added to batch query and threaded through to `analyze_session`
+- [ ] PSA Retry: `account_id` added to batch query and threaded through to `retry_failed_push`
+- [ ] Maintenance Schedule Firing: all queries include `account_id`; `Session` creation sets `account_id` after Phase 1 migration
+- [ ] AI Conversation Expiry: cross-tenant approval comment added to code
+- [ ] All jobs reviewed against this policy before Phase 3 (RLS enable)
+
+---
+
+## Section 9: Open Questions
 
 | Question | Impact | Owner |
 |---|---|---|
@@ -550,6 +627,11 @@ Everything that must be in place before writing feature code on any tenant-data
 - [ ] Alembic uses `DATABASE_ADMIN_URL`
 - [ ] `get_db()` executes `SET LOCAL app.current_account_id` per request inside transaction
 - [ ] Super admin endpoints use admin connection
+- [ ] All background jobs updated to use `resolutionflow_admin` role (see Section 8)
+- [ ] Knowledge Flywheel: `account_id` threaded through batch query and `analyze_session`
+- [ ] PSA Retry: `account_id` threaded through batch query and `retry_failed_push`
+- [ ] Maintenance Schedule: all queries include `account_id`; `Session` creation sets `account_id`
+- [ ] AI Conversation Expiry: cross-tenant approval comment added to code
 - [ ] `test_rls_isolation.py` written with ~160 test cases
 - [ ] All RLS tests pass (100%)
 - [ ] Connection pool reuse test passes