docs: record §3.4 PlayAlbum queue seam closure (P11 W1 follow-up)

CutDetail Play affordances now consume IQueueService.PlayRelease; annotate
PLAN.md §11 landed note and add COMPLETED.md entry.

COMPLETED.md

@@ -8,6 +8,16 @@ Newest entries at the top. Group by phase/wave header (mirroring `PLAN.md` / `CM
 
 ## Phase 11 — Public Site Enhancements
 
+### §3.4 PlayAlbum queue seam — wired (follow-up to 11.A + 11.F)
+
+**Landed:** 2026-06-16 on dev.
+
+- **What:** The §3.4 integration seam between 11.A (`/cuts/{id}`) and 11.F (`IQueueService`) is now closed. `CutDetail.razor` consumes the cascaded `IQueueService`: header Play calls `Queue.PlayRelease(ViewModel.Tracks, 0)` (loads the full album as an ordered queue starting at track 0); per-row play calls `Queue.PlayRelease(ViewModel.Tracks, index)` (album continues from the chosen track). The currently-playing row still toggles play/pause via `IPlayerService.TogglePlayPause`. Null-safe fallback to `PlayerService.SelectTrackStreaming` is retained for prerender/non-interactive contexts where the queue cascade is absent. Consumption-only — no changes to `IQueueService`, `QueueService`, the player, or `AudioPlayerProvider`.
+- **Why:** 11.A shipped with a documented one-line seam in `PlayAlbum()` noting the future swap to `IQueueService.PlayRelease`. 11.F landed the queue. This follow-up closes the seam so the Cut detail page actually plays the full album as an ordered queue rather than single-track only.
+- **Shape:** `CutDetail.razor` (`DeepDrftPublic.Client/Pages/`) adds `[CascadingParameter] public IQueueService? Queue { get; set; }` and rewrites `PlayAlbum()` and `PlayTrack()` to branch on `Queue is not null` before falling back to direct `SelectTrackStreaming`.
+
+---
+
 ### 11.A — `/cuts/{id}` album-detail page
 
 **Landed:** 2026-06-16 on dev.

PLAN.md

@@ -226,7 +226,7 @@ Sequenced as **seven waves**; the critical path is `11.A → 11.B → 11.C`, wit
 - **11.F — queue model.** `IQueueService` above the single-slot player + one new player `TrackEnded` hook + player-bar skip controls. **Free-floating, can start cold day one.** Gates the Cuts "play album" affordance (11.A header Play). **Preload (§1.3 half b) stays OUT** — design the seam, defer the feature.
 - **11.G — release Description schema slice.** New `ReleaseEntity.Description` column + EF migration (**Daniel-gated apply**), `ReleaseDto` mirror, `TrackConverter` round-trip, write-path plumbing (`UpdateTrackMetadataRequest` + upload form + the unified services, threaded wherever `Genre` is), CMS `AlbumHeaderFields` multiline input (§3d). **Free-floating, can start cold day one** — the only gate is Daniel's migration go-ahead. The **detail-page render is NOT in this wave**: the Cut text block rides 11.A, the Session/Mix block is a small additive touch to those existing pages. Both degrade cleanly (null Description renders nothing), so render & schema can land in either order.
 
-**Landed:** 11.A (2026-06-16); 11.F (2026-06-16); 11.G (2026-06-16). Migration `20260616035252_AddReleaseDescription` authored but not yet applied (Daniel-gated). Tracks 11.B, 11.C, 11.D, 11.E remain open.
+**Landed:** 11.A (2026-06-16); 11.F (2026-06-16); 11.G (2026-06-16). The §3.4 PlayAlbum→`IQueueService` seam (deferred in 11.A, awaiting 11.F) is now closed: `CutDetail.razor` consumes the cascaded `IQueueService` — header Play calls `Queue.PlayRelease(ViewModel.Tracks, 0)`, per-row play calls `Queue.PlayRelease(ViewModel.Tracks, index)`, currently-playing row toggles play/pause, null-safe fallback to `SelectTrackStreaming` when the queue cascade is absent (2026-06-16). Migration `20260616035252_AddReleaseDescription` authored but not yet applied (Daniel-gated). Tracks 11.B, 11.C, 11.D, 11.E remain open.
 
 **Dependency shape:** `11.A → 11.B → 11.C`; `11.B → 11.E`; **11.D, 11.F, 11.G parallel** (11.D coordinates with 11.C on `ArchiveView`; 11.F's "play album" is consumed by 11.A; 11.G's Description render rides 11.A + a Session/Mix touch, degrading on null). The cold-start items are **11.A**, **11.F**, and **11.G** — kick 11.A + 11.F off first so "play album" works on first ship of the Cut page; 11.G runs alongside on its own track.