feat(R3-W4): ground transitions + lifecycle verbatim; K-fix18 DELETED (closes J8, J10, J11-shape, J12, J13, J18, J19)

Core (dedicated agent, independently reviewed): HitGround 0x00528ac0 /
LeaveGround 0x00528b00 verbatim (creature+gravity gates, the
RemoveLinkAnimations seam — K-fix18's retail mechanism — velocity via
GetLeaveGroundVelocity with the autonomous flag, jump-state resets,
apply_current_movement re-sync); enter_default_state 0x00528c80 per A8
(fresh states, InitializeMotionTables seam, sentinel APPENDED without
draining pending_motions — pinned, Initted=1, LeaveGround tail);
Initted gates; the A3 IsThePlayer dual dispatch in
apply_current_movement / ReportExhaustion / SetWeenieObject /
SetPhysicsObject (a remote player routes INTERPRETED — the
ACE-divergence pin); set_hold_run 0x00528b70 + SetHoldKey 0x00528bb0
(XOR guard, None-only-from-Run); adjust_motion creature guard wired
(TS-34 retired); PhysicsBody.LastMoveWasAutonomous +
set_local_velocity(autonomous). Port discovery: retail's
apply_raw_movement 0x005287e0 / apply_interpreted_movement 0x00528600
ARE the already-shipped D6.2a/funnel functions — the dual dispatch
composes them instead of duplicating.

App cutover (orchestrator): the skipTransitionLink flag + both K-fix18
call sites DELETED (AP-74 retired). MotionInterpreter.DefaultSink routes
apply_current_movement's interpreted branch through the REAL funnel
dispatch when a sink is bound — so a remote's LeaveGround engages
Falling via the contact-gated funnel, replacing the forced SetCycle
(J19); the per-remote MotionTableDispatchSink is now PERSISTENT
(EnsureRemoteMotionBindings: DefaultSink + RemoveLinkAnimations +
InitializeMotionTables seams, idempotent from both the UM and
VectorUpdate paths; wire velocity re-applied after LeaveGround so it
stays authoritative). Player: seams bound to the player sequencer; the
controller's grounded→airborne EDGE now fires LeaveGround (jump()
clears OnWalkable and the same frame's transition detection fires it —
retail's order; walk-off-a-ledge gets the momentum fallback + link
strip it never had); the manual jump-block LeaveGround deleted;
LastMoveWasAutonomous set at the controller chokepoint (W6 refines).

Trace S8 re-expressed as the retail mechanism (Falling dispatch +
RemoveAllLinkAnimations = same final state the flag produced). 43 new
lifecycle tests. Registers: TS-34 + AP-74 retired; TS-38, AP-77, AP-78
added. Full suite: 3,665 passed. Live smoke: in-world clean.

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

src/AcDream.Core/Physics/PhysicsBody.cs

@@ -245,6 +245,24 @@ public sealed class PhysicsBody
     /// </summary>
     public bool IsFullyConstrained { get; set; }
 
+    /// <summary>
+    /// R3-W4 — retail <c>CPhysicsObj::last_move_was_autonomous</c>, read by
+    /// <c>CPhysicsObj::movement_is_autonomous</c> (0x0050eb30, decomp §7a
+    /// @276443: <c>return this-&gt;last_move_was_autonomous;</c>). Gates the
+    /// A3 dual-dispatch predicate in <c>MotionInterpreter.apply_current_movement</c>/
+    /// <c>ReportExhaustion</c>/<c>SetWeenieObject</c>/<c>SetPhysicsObject</c>:
+    /// true means the last motion on this body was locally-simulated
+    /// (player input / local prediction), false means it was a
+    /// server-driven dead-reckoning update. Set true at the local-player
+    /// input chokepoint (App layer — <c>PlayerMovementController</c>);
+    /// left false (the safe default — routes to
+    /// <c>apply_interpreted_movement</c>) for DR-applied remote updates.
+    /// <see cref="MotionInterpreter.LeaveGround"/> also sets this true
+    /// itself: retail's <c>set_local_velocity(&amp;var_c, 1)</c> call passes
+    /// the autonomous flag literal <c>1</c> (raw @305763-305765).
+    /// </summary>
+    public bool LastMoveWasAutonomous { get; set; }
+
     // ── convenience helpers ────────────────────────────────────────────────
 
     public bool HasGravity  => State.HasFlag(PhysicsStateFlags.Gravity);
@@ -324,10 +342,23 @@ public sealed class PhysicsBody
     ///     worldY = col0.y*localX + col1.y*localY + col2.y*localZ
     ///     worldZ = col0.z*localX + col1.z*localY + col2.z*localZ
     ///   We replicate this as a Quaternion rotation, which is equivalent.
+    ///
+    /// <para>
+    /// R3-W4: retail's <c>set_local_velocity</c> takes a second
+    /// <c>autonomous</c> arg (<c>CPhysicsObj::set_local_velocity</c>,
+    /// stores it to <see cref="LastMoveWasAutonomous"/> — read by
+    /// <c>CPhysicsObj::movement_is_autonomous</c>, the A3 dual-dispatch
+    /// predicate). Defaults to <c>false</c> to preserve every pre-W4 call
+    /// site's behavior (server/interpreted-driven callers never asserted
+    /// autonomy); <see cref="MotionInterpreter.LeaveGround"/> is the one
+    /// caller that passes <c>true</c> (raw @305763-305765,
+    /// <c>set_local_velocity(&amp;var_c, 1)</c>).
+    /// </para>
     /// </summary>
-    public void set_local_velocity(Vector3 localVelocity)
+    public void set_local_velocity(Vector3 localVelocity, bool autonomous = false)
     {
         var worldVelocity = Vector3.Transform(localVelocity, Orientation);
+        LastMoveWasAutonomous = autonomous;
         set_velocity(worldVelocity);
     }