fix: FPS character controller review fixes

- Camera: Make view bob additive to crouch eye height (was overwriting position.y)
- Camera: Sustain sprint FOV kick while sprinting (was recovering immediately)
- Camera: Remove unused _was_sprinting variable
- Controller: Use just_pressed for jump (was sending every frame while held)
- Controller: Direct input dict assignment instead of merge() to avoid alloc
- Controller: Add clearer comments on server-authoritative readback mode

client/characters/character/fps_camera.gd

@@ -70,12 +70,12 @@ var _weapon_rest: Transform3D
 var _base_fov: float = 75.0
 var _current_fov_offset: float = 0.0
 
-## Sway state.
+## Sway state (used as both current value and interpolation target).
 var _sway_current: Vector2 = Vector2.ZERO
 var _sway_target: Vector2 = Vector2.ZERO
 
-## Sprint state cache (detect transition for FOV kick).
-var _was_sprinting: bool = false
+## Base eye Y set by parent controller's crouch logic (for additive bob).
+var _base_eye_y: float = 0.0
 
 # ---------------------------------------------------------------------------
 # Lifecycle
@@ -100,6 +100,10 @@ func _process(delta: float) -> void:
 	if _controller == null:
 		return
 
+	# Capture the eye height set by parent controller's crouch logic
+	# before we apply view bob offsets (which must be additive).
+	_base_eye_y = position.y
+
 	# FOV management
 	_update_fov(delta)
 
@@ -119,16 +123,15 @@ func _process(delta: float) -> void:
 func _update_fov(delta: float) -> void:
 	var target_offset: float = 0.0
 
-	# Sprint FOV kick
-	if _controller.is_sprinting() and not _was_sprinting:
+	# Sprint FOV kick — sustained while sprinting (not just on transition)
+	if _controller.is_sprinting():
 		target_offset = sprint_fov_kick
 
 	# Shoot FOV kick is triggered externally via trigger_shoot_fov()
+	# and decays toward the sprint/walk target naturally via move_toward.
 	_current_fov_offset = move_toward(_current_fov_offset, target_offset, fov_recovery_speed * delta)
 	fov = _base_fov + _current_fov_offset
 
-	_was_sprinting = _controller.is_sprinting()
-
 
 # ---------------------------------------------------------------------------
 # View bobbing
@@ -157,7 +160,9 @@ func _update_bob(delta: float) -> void:
 
 	# Apply bob to camera position (relative to parent's eye offset)
 	position.x = _bob_offset.x
-	position.y = _bob_offset.y
+	# Bob is additive on Y so it does NOT overwrite the crouch eye height
+	# set by the parent FPSCharacterController._update_crouch().
+	position.y = _base_eye_y + _bob_offset.y
 
 
 # ---------------------------------------------------------------------------

client/characters/character/fps_character_controller.gd

@@ -186,7 +186,7 @@ func _unhandled_input(event: InputEvent) -> void:
 func _physics_process(delta: float) -> void:
 	# 1. Capture input state
 	var input_dir := _get_move_direction()
-	var jump_pressed := Input.is_action_just_pressed(&"jump") or Input.is_action_pressed(&"jump")
+	var jump_pressed := Input.is_action_just_pressed(&"jump")
 	var sprint_pressed := Input.is_action_pressed(&"sprint")
 	var crouch_pressed := Input.is_action_pressed(&"crouch")
 	var shoot_pressed := _mouse_clicked_this_frame or Input.is_action_pressed(&"shoot")
@@ -229,18 +229,16 @@ func _physics_process(delta: float) -> void:
 
 	# 6. Send input to simulation server
 	if _server != null and entity_id >= 0:
-		# Build input for SimulationServer
-		_input_dict.merge({
-			"move_direction": input_dir,
-			"look_yaw": rad_to_deg(_yaw),
-			"look_pitch": rad_to_deg(_pitch),
-			"jump": jump_pressed,
-			"crouch": _crouch_active,
-			"sprint": _sprint_active,
-			"shoot": shoot_pressed,
-			"aim": aim_pressed,
-			"input_sequence": _input_sequence,
-		}, true)
+		# Build input for SimulationServer (mutate cached dict to avoid alloc)
+		_input_dict["move_direction"] = input_dir
+		_input_dict["look_yaw"] = rad_to_deg(_yaw)
+		_input_dict["look_pitch"] = rad_to_deg(_pitch)
+		_input_dict["jump"] = jump_pressed
+		_input_dict["crouch"] = _crouch_active
+		_input_dict["sprint"] = _sprint_active
+		_input_dict["shoot"] = shoot_pressed
+		_input_dict["aim"] = aim_pressed
+		_input_dict["input_sequence"] = _input_sequence
 
 		_server.apply_input(entity_id, _input_dict)
 
@@ -251,14 +249,17 @@ func _physics_process(delta: float) -> void:
 
 	# 7. Read server state back (for local simulation / listen server)
 	#    The SimulationServer.tick() call happens in the game manager / network layer.
-	#    Here we read the entity's canonical position from the server.
+	#    Here we optionally read the entity's canonical position from the server.
+	#    NOTE: On a dedicated client, position comes from the network replication
+	#    layer (server snapshot), not from direct server entity access.
+	#    On a listen server (host+client same process) or in standalone mode,
+	#    reading position directly from the server entity is correct.
 	if _server != null and entity_id >= 0:
 		var entity = _server.get_entity(entity_id)
 		if entity != null and entity.is_alive():
 			# Server position is ground truth — apply it to the visual body
+			# (only correct on listen-server; pure clients must use replication)
 			global_position = entity.position
-			# Note: rotation is already set from yaw/pitch above (client-side)
-			# On a pure client the server snapshot override is applied differently.
 	else:
 		# Standalone mode: do local CharacterBody3D physics
 		_move_local(input_dir, delta, jump_pressed)