docs(12): create phase plan

.planning/phases/12-p-ytarium-api-collections-and-albums/12-RESEARCH.md

@@ -534,9 +534,11 @@ func CollectionKey(appKey string, id uint) string {
 | A5 | The publication normalizer does not mask the album subtree's `created_at`/`updated_at` | Finding 5 | If it already does, there is less tide work |
 | A6 | `isSiteAdmin` can be false for everyone in Phase 12 because the Go user plugin has no `users_groups` | Open Q3 | `can_manage_org`/`can_use_ai`/`can_import_discogs` are wrong for site admins |
 
-## Open Questions
+## Open Questions (RESOLVED)
 
-None of these is decided yet. Each needs the user's confirmation at the plan-count checkpoint.
+All six were decided by the user at the plan-count checkpoint on 2026-10-02 and recorded in 12-CONTEXT.md:
+Q1 → D-19 (Scout recount), Q2 → D-20 (port realtime/channels), Q3 → D-25 (option b: add user groups, signed off),
+Q4 → D-22 (match PHP prefix), Q5 → D-24 (register webp), Q6 → D-23 (encrypt token in job args).
 
 1. **D-16 correction (Finding 1).**
    - What we know: installed Scout v10.25.0 recounts `total` in SQL over min(found, 1000) re-gated ids.