feat: overhaul movement for flow — momentum-preserving states, smooth crouch, landing feel

- Quake-style air-strafe accelerate (real speed gain from strafing; external
  speed from dash/rockets never clamped)
- Wall run: keeps entry momentum (incl. upward carry), accelerates along the
  wall instead of hard-setting velocity, gravity fades in over the run
- Slide: slope physics (gravity projected along floor accelerates downhill),
  flat-ground decel instead of multiplicative friction, entry boost, direct
  slide->wallrun and slide->dash transitions
- Dash: cooldown 10s -> 2s, per-player (was a static shared across instances),
  momentum fully kept on exit, FOV punch event
- Grapple: taut pendulum with active rope control (W reels in, S pays out),
  release keeps swing energy
- Wall climb: carries upward momentum in, jump-off kick, shared vault helper
- Crouch capsule: single owner in the machine, smoothly lerped, ceiling check;
  camera eye height follows via crouch factor (no more head snapping)
- Landing: machine emits 'land' events scaled by impact; camera dip + pitched
  down thud; footsteps get pitch variation
- Camera rig: event-driven (land dip, dash FOV kick, vault pitch impulse),
  slide roll tilt
- Model: Jump vs Fall split by vertical velocity, Land one-shot on heavy
  landings, wall-run body lean (synced to remotes via synced_wall_side)

Co-Authored-By: Claude Fable 5 <[email protected]>

movement/player_movement_controller.gd

@@ -74,6 +74,7 @@ var synced_is_crouching: bool = false
 var synced_position: Vector3 = Vector3.ZERO
 var synced_velocity: Vector3 = Vector3.ZERO
 var synced_is_ads: bool = false
+var synced_wall_side: float = 0.0  # -1 wall left, +1 wall right (wall-run lean)
 @export var synced_skin_id: String = ""
 @export var synced_weapon_path: String = ""
 
@@ -876,11 +877,14 @@ func _physics_process(_delta: float) -> void:
 		if visual.has_method("set_locomotion"):
 			var d := _local_move_dir()
 			visual.set_locomotion(d.x, d.y, 1.0 if synced_is_ads else 0.0)
+		if visual.has_method("set_wall_side"):
+			visual.set_wall_side(sm.wall_side)
 
 	# Publish state for remote peers
 	synced_movement_state = sm.current_state
 	synced_movement_speed = Vector2(velocity.x, velocity.z).length()
 	synced_is_crouching = sm.input_crouch
+	synced_wall_side = sm.wall_side
 	synced_position = position
 	synced_velocity = velocity
 
@@ -914,6 +918,14 @@ func _on_movement_event(ev: String, data: Dictionary) -> void:
 		grapple_shoot_player.play()
 	elif ev == "grapple_latch":
 		grapple_latch_player.play()
+	elif ev == "land":
+		# Landing thud: reuse the footstep sample, pitched down and louder
+		# with impact. Ground state resets pitch/volume before each step.
+		if footstep_player:
+			var heavy: bool = data.get("heavy", false)
+			footstep_player.pitch_scale = 0.55 if heavy else 0.7
+			footstep_player.volume_db = 2.0 if heavy else -2.0
+			footstep_player.play()
 
 func _process(delta: float) -> void:
 	# Remote players: interpolate toward the owner's synced transform and
@@ -946,6 +958,8 @@ func _process(delta: float) -> void:
 			if visual.has_method("set_locomotion"):
 				var d := _local_move_dir()
 				visual.set_locomotion(d.x, d.y, 1.0 if synced_is_ads else 0.0)
+			if visual.has_method("set_wall_side"):
+				visual.set_wall_side(synced_wall_side)
 			# Check for weapon changes
 			if synced_weapon_path != "" and synced_weapon_path != visual.get_meta("current_weapon_path", ""):
 				visual.set_weapon(synced_weapon_path)