docs: session memory — evening animation investigation + agent dispatch

Captures the diagnosis chain (wrong-first-guess -> parser offset bug
-> handler rewrite -> ACE-confirmed observer-side inference), the
Agent A animation-overhaul merge (10 commits, dead-reckoning + speed
scaling + Commands list + sequence-wide velocity + soft-snap), the
pending Agent B sky/weather/lighting branch, and the orthogonal
wire-layer adds (SocialActions, InventoryActions, AppraiseInfo profile
blobs, 9 extra GameEvent parsers).

Current tree state: 684 tests passing (192 Core.Net + 492 Core),
build green, animation overhaul live on main.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

memory/project_session_2026_04_18.md

@@ -12,6 +12,110 @@ User went AFK with direction:
 - Reminder: when connecting to the live ACE server, must log out of
   the previous session first; server is always up.
 
+## Delta: 30+ commits on main, 470 → 684 tests (+214), continuing
+
+**Status at the time of this update**: continuing the session. The earlier
+wire-layer push (E.1-H.2 + AppraiseInfoParser) is stable. The evening
+was dominated by a remote-player animation bug investigation + deep-dive
+agent dispatch.
+
+## Investigation chain
+
+User reported: "other players don't render properly now. Wrong clothes,
+just look like they are lagging forward with run animation. And when
+they stop, their running animation is still on."
+
+Iterated on the diagnosis:
+
+1. **First guess (wrong)**: today's AnimationSequencer rewrite caused
+   it. User tested a d910d57 worktree baseline and confirmed "No its
+   basically the same" — pre-existing bug, not a regression.
+2. **Parser dump revealed**: the UpdateMotion parser had a 2-byte
+   offset error in its MovementData header skip. ACE's `Align()`
+   pads based on **absolute stream length** (15 → 16, pad 1 byte,
+   header total 6 bytes), not relative-to-block (which would pad 3 =
+   header 8). The old parser assumed 8 → every subsequent field
+   shifted by 2 → stance + command decoded as the packed-flags dword.
+3. **Handler rewrite**: OnLiveMotionUpdated now uses SetCycle directly
+   instead of GetIdleCycle (which ignored command when stance==0);
+   preserves current style/motion with "no-change" semantics; full
+   MotionCommand reconstruction from 16-bit wire values.
+4. **ACE source confirmed**: Player_Tick.cs:368 — "the client will
+   never send a 'client released forward' MoveToState in this
+   scenario unfortunately. because of this, it's better to have the
+   'client blip forward' bug without it." → Server never broadcasts
+   explicit Ready. Observer must infer stopped from position deltas.
+
+Then dispatched two Opus-4.7 parallel agents with high-effort research
++ implementation mandates per user direction ("ultrathink", "super
+high effort"):
+
+## Agent A — retail animation overhaul (MERGED to main)
+
+10 commits on worktree-agent-ae8eec87, +32 tests (628→660 before my
+orthogonal adds). Shipped:
+
+- **MultiplyCyclicFramerate** on AnimationSequencer — mid-cycle speed
+  change without restart. Fixes "animation speed doesn't scale with run
+  rate" for both the local player and remote observers.
+- **Dead-reckoning** per remote entity: EMA-smoothed velocity from
+  consecutive UpdatePosition deltas, per-tick integration using the
+  sequencer's current velocity rotated by entity orientation, clamp
+  radius to prevent runaway on lost updates. Fixes "lagging forward"
+  — remote chars now move smoothly between position updates.
+- **Commands[] list parsing** — the InterpretedMotionState tail list
+  (MotionItem records) was completely unparsed. NPCs transmit waves,
+  attacks, death throes via this list. Now routed through PlayAction
+  (for Actions/Modifiers/Emotes) or SetCycle (SubStates).
+- **MotionCommandResolver** — reflects the DatReaderWriter.Enums.MotionCommand
+  enum to reconstruct the full 32-bit command value from the 16-bit
+  wire field. Prior ad-hoc OR of 0x40000000 sometimes produced
+  invalid commands.
+- **Sequence-wide Velocity/Omega** — was per-node via lookup, broke
+  during link transitions (cycle's velocity wasn't surfaced while a
+  link played). Now matches ACE Sequence.Velocity (last-added-wins,
+  retained across link/cycle boundary).
+- **Omega integration to entity rotation** — TurnRight/TurnLeft cycles
+  now smoothly rotate the entity each tick between server updates.
+- **Soft-snap residual** — server UpdatePosition is authoritative but
+  blended over ~300ms so corrections don't look like teleports.
+- **Stop detection hardening** — 300ms position-stale + velocity-dead
+  double signal; dedup on respawn clears stale dead-reckon state.
+
+### Deferred by Agent A
+
+- PosFrames root motion drain (most AC locomotion uses MotionData.Velocity)
+- Full MotionState struct port (Modifier list, Action queue, substateMod)
+- AttackHook → combat damage frame sink
+- ReplaceObjectHook → weapon draw mesh swap
+- Stance transition double-link chain (HandCombat → SwordCombat multi-link)
+
+## Agent B — sky / weather / lighting (in progress)
+
+Still running. When it completes, will ship:
+- SkyRenderer with retail GfxObj-based sky objects (not a textured sphere)
+- WeatherRenderer (rain/snow/fog via existing ParticleSystem)
+- Dynamic-lighting shader UBO (8-light UBO per R13 §12.3)
+- Torch/fireplace/spell-aura LightSource registration via SetLightHook
+
+## Additional orthogonal work this session (merged on main)
+
+- **UpdateMotion parser fix** — 6-byte header (not 8). Committed
+  before agent dispatch.
+- **GameWindow stop detection** — 400ms position-stale → Ready (later
+  superseded by Agent A's 300ms + velocity-dead version).
+- **AppraiseInfoParser profile blobs** — ArmorProfile / CreatureProfile
+  / WeaponProfile / ArmorLevels / enchantment bitfields. +6 tests.
+- **SocialActions** — QueryHealth (0x01BF), PingRequest (0x01E9),
+  FellowshipCreate/Quit/Dismiss/Recruit/Update, SetCharacterOptions,
+  AddChannel/RemoveChannel. +10 tests.
+- **InventoryActions** — StackableMerge/Split×3, GiveObjectRequest,
+  AddShortcut, RemoveShortcut, TeleToPoi. +8 tests.
+- **9 more GameEvent parsers** — UseDone, PutObjectIn3D,
+  InventoryServerSaveFailed, CloseGroundContainer, TradeFailure,
+  AddToTrade, AcceptTrade, QueryItemManaResponse,
+  CharacterConfirmationRequest.
+
 ## Delta: 19 commits on main, 470 → 628 tests (+158)
 
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