fix(client): re-assert mouse facing after each follow step — vision-cone flap mitigation (T-1088)

Live finding: during a path-follow the cone snapped to path-forward on every
accepted step (server facing_from_delta overwrites Facing; the change-gated
SetFacing never re-sends an unchanged octant) and stayed there until the
mouse crossed an octant boundary. The follower now re-asserts the current
mouse octant 100ms (~2 ticks) after each emitted step — same-tick re-asserts
lose, movement wins within a tick — shrinking the flap to a ~100ms blip.
Full stability needs server-side aim-lock: filed T-1093 (Q-084's walk-vs-aim
split, now with play evidence); wire semantics untouched per the sidequest's
presentation-layer constraint.

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

client/scripts/sandbox/path_follower.gd

@@ -48,7 +48,14 @@ enum Mode { NORMAL, SPRINT, CROUCH }
 ## last element. Empty while inactive.
 var _path: Array[Vector3i] = []
 var _goal: Vector3i = Vector3i.ZERO
+## T-1088 follow-facing: two server ticks (50 ms each) after an emitted step —
+## past the tick that applies the move (whose facing_from_delta would win) but
+## as soon after as the wire allows.
+const FACING_REASSERT_DELAY_MS := 100
+
 var _active: bool = false
+## 0 = nothing pending; else the msec deadline for the post-step facing re-assert.
+var _reassert_at_ms: int = 0
 
 var _mode: int = Mode.NORMAL
 ## SPRINT only: the pre-sprint stance (kept for readability/debug) and the exact
@@ -120,6 +127,13 @@ func cancel() -> void:
 func tick(current_tile: Vector3i, is_floor: Callable) -> void:
 	if not _active:
 		return
+	# T-1088 follow-facing: the server overwrote Facing from this follow's last
+	# accepted step — re-assert the mouse octant once the overwrite tick has
+	# passed (~2 server ticks; a same-tick re-assert loses, movement wins within
+	# a tick). Keeps the vision cone on the mouse while the body walks the path.
+	if _reassert_at_ms > 0 and Time.get_ticks_msec() >= _reassert_at_ms:
+		_reassert_at_ms = 0
+		InputMapper.reassert_facing()
 	# Cancel (no stance change): input suppression — dialogue / free camera.
 	if GameState.dialogue_active or GameState.free_camera_mode:
 		cancel()
@@ -147,7 +161,8 @@ func tick(current_tile: Vector3i, is_floor: Callable) -> void:
 	# the 200 ms cadence automatically — the character accelerates into the sprint).
 	var next_tile: Vector3i = _path[idx + 1]
 	var delta := Vector2i(next_tile.x - current_tile.x, next_tile.y - current_tile.y)
-	InputMapper.queue_move_step(delta)
+	if InputMapper.queue_move_step(delta):
+		_reassert_at_ms = Time.get_ticks_msec() + FACING_REASSERT_DELAY_MS
 
 
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