feat(R1-P2): verbatim CSequence container + list surgery

CSequence (Core/Physics/Motion): anim-node list with retail's exact
cursor semantics —
- append_animation (0x00525510): first_cyclic slides to the JUST-
  APPENDED node on EVERY call (the cyclic tail is always the last
  appended node); curr_anim seeds to head + get_starting_frame only
  when null; unresolvable anims discarded (G10);
- remove_cyclic_anims (0x00524e40): removed curr_anim snaps BACK to
  prev at get_ending_frame (or 0.0); first_cyclic = new tail;
- remove_link_animations/remove_all_link_animations (0x00524be0/
  0x00524ca0): removed curr_anim snaps FORWARD to first_cyclic at
  get_starting_frame (G11);
- apricot (0x00524b40, PDB-verified retail name): consumed-head trim
  bounded by curr_anim AND first_cyclic;
- clear (0x005255b0) resets placement fields too — raw body is
  authority over the gap map's G20 note;
- sequence-level velocity/omega with set/combine/subtract (G12);
- multiply_cyclic_animation_fr touches framerates ONLY (G13 —
  velocity rescale belongs to R2's change_cycle_speed composite);
- placement frame family + floored accessors (G14).

Register: AD-33 (double vs x87 long double frame_number, G15),
AD-34 (managed LinkedList vs intrusive DLList).

17 list-surgery state-table tests; 39 total R1 tests green.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/architecture/retail-divergence-register.md

@@ -61,7 +61,7 @@ accepted-divergence entries (#96, #49, #50).
 
 ---
 
-## 2. Adaptation (AD) — 32 rows
+## 2. Adaptation (AD) — 34 rows
 
 | # | Divergence | Where (file:line) | Why it is safe / justified | Risk if assumption breaks | Retail oracle |
 |---|---|---|---|---|---|
@@ -96,6 +96,8 @@ accepted-divergence entries (#96, #49, #50).
 | AD-30 | Cell-march preserves seed landblock id when `TryGetTerrainOrigin` returns false for an outdoor seed (#145 D, 2026-06-22): `BuildCellSetAndPickContaining` returns `currentCellId` verbatim rather than marching via `blockOrigin=(0,0,0)`; retail never encounters this state (cells stored block-local, no streaming-gap concept) | `src/AcDream.Core/Physics/CellTransit.cs:765` | Equivalence argument: "preserve-verbatim when unregistered" is the same contract as `PhysicsEngine.Resolve`'s NO-LANDBLOCK branch; the player's cell stays the last known-correct cell until the landblock's terrain registers — no march, no lbX=0 wire | A body whose seed landblock is genuinely absent for >1 physics tick holds its last-known cell rather than discovering the true containing cell; transient only — corrects the instant terrain registers; an indoor seed is explicitly excluded from the guard (outdoor low < 0x100 gate) | `CObjCell::find_cell_list` + block-local storage (retail has no streaming gap); `TryGetTerrainOrigin` pc path |
 | AD-31 | Teleport transit covered by a full-screen black FADE (`FadeOverlay` + `TeleportAnimSequencer`) instead of retail's 3D portal-tunnel swirl (2026-06-22, spec C). Opaque black holds through the tunnel states; the world ramps back in on `WorldFadeIn`. | `src/AcDream.App/Rendering/FadeOverlay.cs` + `GameWindow.cs` (TAS transit tick; `_teleportFadeAlpha = ShowTunnel ? 1 : FadeAlpha`) | The fade is a functional cover that hides the (now-fast) destination load + the post-materialization object flood; the TAS state machine + golden timing constants are retail-verbatim — only the tunnel *graphic* is approximated. Sibling to AP-49 (fade-curve). | Visual-only: the transit shows a black cover, not the animated swirl. Retire by porting the `gmSmartBoxUI` 3D tunnel render. | `gmSmartBoxUI::UseTime` 0x004d6e30 (tunnel render, unported); `TELEPORT_ANIM_*` golden constants (spec §2.1) |
 | AD-32 | Movement-event staleness gate ADOPTS a newer-incarnation instance stamp and applies the event immediately; retail queues the blob for the not-yet-created object (`SmartBox::QueueBlobForObject`, dispatch return 4) and replays it once that incarnation exists (L.2g S1, 2026-07-02) | `src/AcDream.Core/Physics/MotionSequenceGate.cs:105` | acdream has no per-object blob queue; a newer instance seq means the new incarnation's CreateObject is in flight, and that CreateObject re-seeds the same gate (advance-only), so old-incarnation stragglers still drop | A motion event for a new incarnation applies to the OLD body for up to one CreateObject round-trip — brief wrong-cycle flicker on respawn/re-instance if the new incarnation's motion table differs | 0xF74C dispatch pc:357214-357239 (`is_newer(update_times[8], seq)` + `QueueBlobForObject`) |
+| AD-33 | `CSequence.frame_number` at C# `double` (64-bit); retail is x87 `long double` (80-bit extended) — every frame-boundary comparison ran at extended precision on retail (Phase R1, 2026-07-02) | `src/AcDream.Core/Physics/Motion/CSequence.cs` (`FrameNumber`) | `double` is the widest C# float type; the R1 port removes ACE-style boundary epsilons so comparisons are exact-int against bare boundaries, minimizing ULP sensitivity (ACE's `float` is far worse) | A frame landing within 1 double-ULP of an integer boundary could classify differently than retail's 80-bit compare — sub-frame timing skew at pathological framerate×dt combinations | `acclient.h:30747` (`long double frame_number`) |
+| AD-34 | Retail's intrusive `DLListBase`/`DLListData` anim-node list is a managed `LinkedList<AnimSequenceNode>`; node identity via `LinkedListNode<>` references (Phase R1, 2026-07-02) | `src/AcDream.Core/Physics/Motion/CSequence.cs` (`_animList`) | Same topology + cursor semantics (curr_anim/first_cyclic are node references); unlink/delete becomes `Remove(node)`; conformance tests pin the surgery state tables | Any retail behavior depending on the −4 pointer adjustment or node memory reuse (none observed in the decomp) would diverge | `acclient.h` DLListBase; `r1-csequence-decomp.md` §0 |
 
 ---