Add prop interaction system and throw mechanics specification

- Introduced `stickman_prop_interactor.gd` to manage prop interactions.
- Created `phase_11_prop_interactions.md` detailing the design and implementation of prop pickup, drop, and throw mechanics.
- Defined interaction states, action lifecycles, and event triggers for prop handling.
- Specified constraints for throw actions, including target positioning and velocity calculations.
- Established acceptance criteria for prop interactions and lifecycle management.

scripts/stickman_rig.gd

@@ -179,6 +179,7 @@ signal action_finished(action: Dictionary, index: int)
 signal queue_finished                            # queue ran to completion (not on stop)
 signal queue_changed                             # any queue mutation
 signal speech_finished                           # bubble auto-hid after speak()
+signal prop_interaction_event(event_type: String, prop: PropBlock, reason: String)
 
 # ---------------------------------------------------------------------------
 # Internal state
@@ -225,6 +226,7 @@ var source_stk_path: String = ""
 var _locomotion_component: StickmanLocomotion = null
 var _ragdoll_component: StickmanRagdoll = null
 var _action_runner_component: StickmanActionRunner = null
+var _prop_interactor_component: Node = null
 var _simulation_paused: bool = false
 var _phase12_paused_animation: bool = false
 var _phase12_paused_animation_name: StringName = &""
@@ -238,12 +240,15 @@ func _ready() -> void:
 	_locomotion_component = get_node_or_null(NodePath("RigComponents/Locomotion")) as StickmanLocomotion
 	_ragdoll_component = get_node_or_null(NodePath("RigComponents/Ragdoll")) as StickmanRagdoll
 	_action_runner_component = get_node_or_null(NodePath("RigComponents/ActionRunner")) as StickmanActionRunner
+	_prop_interactor_component = get_node_or_null(NodePath("RigComponents/PropInteractor"))
 	if _locomotion_component == null:
 		push_warning("StickmanRig: missing RigComponents/Locomotion; locomotion boundary unavailable.")
 	if _ragdoll_component == null:
 		push_warning("StickmanRig: missing RigComponents/Ragdoll; ragdoll boundary unavailable.")
 	if _action_runner_component == null:
 		push_warning("StickmanRig: missing RigComponents/ActionRunner; action boundary unavailable.")
+	if _prop_interactor_component == null:
+		push_warning("StickmanRig: missing RigComponents/PropInteractor; prop interactions unavailable.")
 	if _locomotion_component != null:
 		_locomotion_component.configure(self)
 		_locomotion_component.arrived.connect(func(target: Vector2) -> void: arrived.emit(target))
@@ -251,8 +256,11 @@ func _ready() -> void:
 		_ragdoll_component.configure(self, _locomotion_component)
 		_ragdoll_component.recovery_requested.connect(func() -> void: request_recovery())
 		_ragdoll_component.state_transition_requested.connect(_set_state)
+	if _prop_interactor_component != null:
+		_prop_interactor_component.call("configure", self, _locomotion_component, Callable())
+		_prop_interactor_component.connect("prop_event", _on_prop_interaction_event)
 	if _action_runner_component != null:
-		_action_runner_component.configure(self, _locomotion_component)
+		_action_runner_component.configure(self, _locomotion_component, _prop_interactor_component)
 		_action_runner_component.action_queue = _pending_action_queue
 		_action_runner_component.action_started.connect(func(action: Dictionary, index: int) -> void: action_started.emit(action, index))
 		_action_runner_component.action_finished.connect(func(action: Dictionary, index: int) -> void: action_finished.emit(action, index))
@@ -315,6 +323,8 @@ func _physics_process(delta: float) -> void:
 		_ragdoll_component.tick_pre_movement(delta, int(state), rest_timeout, auto_recover)
 	if _locomotion_component != null:
 		_locomotion_component.tick_movement(delta, int(state))
+	if _prop_interactor_component != null:
+		_prop_interactor_component.call("tick", delta)
 	if _action_runner_component != null:
 		_action_runner_component.tick(delta, int(state), is_ragdoll_at_rest())
 	_pin_mirrored_head_rotation()
@@ -457,6 +467,8 @@ func _set_state(next_state: int) -> void:
 
 func set_ragdoll(enabled: bool) -> void:
 	if enabled:
+		if _prop_interactor_component != null:
+			_prop_interactor_component.call("disarm_for_ragdoll")
 		if _locomotion_component != null:
 			_locomotion_component.reset_for_ragdoll_handoff()
 		match state:
@@ -480,6 +492,35 @@ func toggle_ragdoll() -> void:
 	set_ragdoll(not is_in_ragdoll())
 
 
+func set_prop_resolver(resolver: Callable) -> void:
+	if _prop_interactor_component != null:
+		_prop_interactor_component.call("configure", self, _locomotion_component, resolver)
+
+
+func start_prop_action(action: Dictionary) -> bool:
+	return bool(_prop_interactor_component.call("start_action", action)) if _prop_interactor_component != null else false
+
+
+func cancel_prop_action() -> void:
+	if _prop_interactor_component != null:
+		_prop_interactor_component.call("cancel_action")
+
+
+func preview_prop_throw(target: Vector2, queue_prefix: Array[Dictionary] = []) -> Dictionary:
+	if _prop_interactor_component == null:
+		return {}
+	return _prop_interactor_component.call("preview_throw", target, queue_prefix)
+
+
+func reset_prop_interactions_for_scene_exit() -> void:
+	if _prop_interactor_component != null:
+		_prop_interactor_component.call("reset_for_scene_exit")
+
+
+func _on_prop_interaction_event(event_type: String, prop: PropBlock, reason: String) -> void:
+	prop_interaction_event.emit(event_type, prop, reason)
+
+
 ## Public stand-up request. No-op unless the rig is in RAGDOLL.
 func request_recovery() -> void:
 	if state == RigState.RAGDOLL and _ragdoll_component != null: