docs(D.2b): re-retire TS-30 in register (restore branch state lost in --theirs merge)

The earlier 'git checkout --theirs' resolution of the register merge conflict
took main's whole file, which reverted two branch-only changes: IA-15 (re-added
in c100484) and the TS-30 retirement. TS-30 (flat-rect UI panels) was retired by
D.2b Spec 1 when UiNineSlicePanel shipped the 8-piece chrome and is doubly moot
now that vitals draw the dat chrome via the importer. Removed the TS-30 row +
its phase-gated reference; TS count 30->29. All section counts now match actual
rows (IA 15 / AD 27 / AP 37 / TS 29 / UN 5).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/architecture/retail-divergence-register.md

@@ -137,7 +137,7 @@ accepted-divergence entries (#96, #49, #50).
 
 ---
 
-## 4. Temporary stopgap (TS) — 30 rows
+## 4. Temporary stopgap (TS) — 29 rows
 
 | # | Divergence | Where (file:line) | Why it is safe / justified | Risk if assumption breaks | Retail oracle |
 |---|---|---|---|---|---|
@@ -170,7 +170,6 @@ accepted-divergence entries (#96, #49, #50).
 | TS-27 | Retransmit handling absent: `RetransmitRequests`/`RejectRetransmit` parsed, but nothing re-sends lost outbound or requests missing inbound sequences (class-doc gap list otherwise stale — ack/position/chat exist) | `src/AcDream.Core.Net/WorldSession.cs:29` | Deferred since the one-shot test harness; dev loop is loopback (no loss) | On any lossy link a dropped fragment is gone forever — entities never spawn, chat vanishes, reassembly stalls; server retransmit requests ignored until session timeout. Stale doc list also misleads readers | PacketHeaderFlags RequestRetransmit 0x1000 / Retransmission 0x1 |
 | TS-28 | LoginComplete sent on PlayerCreate (0xF746) arrival; retail sends it after the portal-space transition animation finishes (no such animation exists yet) | `src/AcDream.Core.Net/Messages/GameActionLoginComplete.cs:30` | acdream has no portal-space animation; "InWorld" phrasing in the file is slightly stale (trigger is PlayerCreate) | Server flips the character out of the loading state and pushes initial updates while the client may still be streaming — server logic assuming retail's load-screen duration fires against a half-initialized client | retail post-EnterWorld flow (holtburger messages.rs:391-422) |
 | TS-29 | Background music (MIDI) + ambient loops not ported: PlayMusic/StopMusic no-op; StartAmbient reserves a handle that never plays | `src/AcDream.App/Audio/OpenAlAudioEngine.cs:331` | Explicitly outside R5 audio-phase scope; a landblock-attached ambient system is planned separately | Silent world where retail has music/atmosphere; code trusting StartAmbient's handle to mean "playing" is already subtly wrong (StopAmbient looks up a never-created source) | retail MIDI + ambient system (r05) |
-| TS-30 | UI panels drawn as flat translucent rectangles + 1 px border; retail composes 9-slice dat sprite backgrounds via LayoutDesc trees | `src/AcDream.App/UI/UiPanel.cs:10` | Development visibility until the D.2b retail-look toolkit consumes the dat assets | Purely visual until D.2b — but pixel-position assumptions built against the placeholder (hit regions, layout constants) may not survive the swap to retail sprite metrics | RenderSurface 0x06xxxxxx 9-slice; LayoutDesc 0x21xxxxxx |
 
 ---
 
@@ -217,8 +216,8 @@ M2 combat must land TS-2 (BspOnlyDispatch terms), TS-5 (CanJump gating),
 TS-23 (PK bits), TS-25 (stance in MoveToState), TS-17 (AttackConditions),
 and revisit AP-13 (ComputeDamage) + AP-24 (jump-charge constant via the
 0x0056ADE0 decompile). Emote work must land TS-24 (command-list packing).
-Membership Stage 2 must land TS-18 (BuildingCellId). D.2b lands TS-30;
+Membership Stage 2 must land TS-18 (BuildingCellId).
-the audio phase lands TS-9/TS-29; the animation-hook layer lands
+The audio phase lands TS-9/TS-29; the animation-hook layer lands
 TS-10/TS-11/TS-12/TS-13/TS-14.
 
 ---