feat(ai): per-NPC npc:set_movement_hold movement lever

gamedata/scripts/lua_help_ex.script

@@ -679,6 +679,7 @@
         void set_hit_redirect(float max, float falloff) // Per-object bonus toward the last attacker in enemy selection, replacing the flat CQB step. max < 0 keeps vanilla. max >= 0 subtracts max*(1 - d2/falloff^2) from the attacker cost within falloff metres, so a close attacker is prioritised and a distant one fades to 0. The victim turns toward the shooter without a forced sighting. Not serialized, re-set on spawn.
         void set_view_distance_factor(float factor) // Per-object view-DISTANCE factor, the range sibling of set_vision_speed: multiplies object_visible_distance's return, composing with the per-state max_view_distance LTX multiplier. 1.0 = vanilla, higher sees farther, negative clamps to 0. Persists while online; re-set on spawn.
         void set_health_restore_boost(float value) // Per-object additive passive health-restore boost: adds value to the condition's m_fV_HealthRestore velocity applied every UpdateHealth while alive (base ~0.00003/s for stalkers), so the entity regenerates HP over time with no item. 0 = vanilla, higher = faster idle regen, negative clamps to 0. Stalkers and monsters (any CEntityAlive). Persists while online; re-set on spawn (condition rebuilt on re-online).
+        void set_movement_hold(bool value) // Per-object movement hold: while true, parse_velocity_mask routes into its Stand branch, so the stalker stays planted (speed 0, movement type Stand) with the path and destination preserved; movement resumes when cleared. false = vanilla. Stalkers only. Not serialized; the caller owns clearing it - a stale true holds the NPC in place indefinitely.
 
         // Stalker NPCs
         function get_enable_anomalies_pathfinding()

src/xrGame/ai/stalker/ai_stalker.cpp

@@ -87,7 +87,8 @@ CAI_Stalker::CAI_Stalker() :
 	m_fire_queue_size_k(-1.f),
 	m_fire_queue_interval_k(-1.f),
 	m_take_items_enabled(true),
-	m_death_sound_enabled(true)
+	m_death_sound_enabled(true),
+	m_movement_hold(false)
 {
 	m_pPhysics_support = NULL;
 	m_animation_manager = NULL;

src/xrGame/ai/stalker/ai_stalker.h

@@ -879,9 +879,13 @@ class CAI_Stalker :
 	IC void death_sound_enabled(bool value);
 	IC bool death_sound_enabled() const;
 
+	IC void movement_hold(bool value);
+	IC bool movement_hold() const;
+
 private:
 	bool m_take_items_enabled;
 	bool m_death_sound_enabled;
+	bool m_movement_hold;
 
 public:
 	smart_cover::cover const* get_current_smart_cover();

src/xrGame/ai/stalker/ai_stalker_inline.h

@@ -212,6 +212,16 @@ IC bool CAI_Stalker::death_sound_enabled() const
 	return (m_death_sound_enabled);
 }
 
+IC void CAI_Stalker::movement_hold(bool value)
+{
+	m_movement_hold = value;
+}
+
+IC bool CAI_Stalker::movement_hold() const
+{
+	return (m_movement_hold);
+}
+
 IC u32 CAI_Stalker::pstl_min_queue_size_far() const
 {
 	return (m_pstl_min_queue_size_far);

src/xrGame/script_game_object.h

@@ -844,6 +844,7 @@ class CScriptGameObject
 	void set_hit_redirect(float max, float falloff);
 	void set_view_distance_factor(float value);
 	void set_health_restore_boost(float value);
+	void set_movement_hold(bool value);
 	bool can_kill_enemy();
 	bool can_kill_member();
 	bool fire_make_sense();

src/xrGame/script_game_object_inventory_owner.cpp

@@ -1957,6 +1957,19 @@ bool CScriptGameObject::is_hit_anim_playing()
 	return (entity_alive->character_physics_support()->is_hit_anim_playing());
 }
 
+void CScriptGameObject::set_movement_hold(bool value)
+{
+	CAI_Stalker* stalker = smart_cast<CAI_Stalker*>(&object());
+	if (!stalker)
+	{
+		ai().script_engine().script_log(ScriptStorage::eLuaMessageTypeError,
+		                                "CAI_Stalker : cannot access class member set_movement_hold!");
+		return;
+	}
+
+	stalker->movement_hold(value);
+}
+
 bool CScriptGameObject::can_kill_enemy()
 {
 	CAI_Stalker* stalker = smart_cast<CAI_Stalker*>(&object());

src/xrGame/script_game_object_script3.cpp

@@ -68,6 +68,7 @@ class_<CScriptGameObject> script_register_game_object2(class_<CScriptGameObject>
 		.def("set_hit_redirect", SAFE_WRAP(&CScriptGameObject::set_hit_redirect))
 		.def("set_view_distance_factor", SAFE_WRAP(&CScriptGameObject::set_view_distance_factor))
 		.def("set_health_restore_boost", SAFE_WRAP(&CScriptGameObject::set_health_restore_boost))
+		.def("set_movement_hold", SAFE_WRAP(&CScriptGameObject::set_movement_hold))
 		.def("active_sound_count", SAFE_WRAP((int (CScriptGameObject::*)())(&CScriptGameObject::active_sound_count)))
 		.def("active_sound_count", SAFE_WRAP((int (CScriptGameObject::*)(bool))(&CScriptGameObject::active_sound_count)))
 		.def("best_cover", SAFE_WRAP(&CScriptGameObject::best_cover))

src/xrGame/stalker_movement_manager_base.cpp

@@ -429,6 +429,7 @@ void stalker_movement_manager_base::parse_velocity_mask(stalker_movement_params&
 	sight_manager_enable_guard guard(object().sight(), true);
 
 	if (
+		object().movement_hold() ||
 		(movement_params.m_movement_type == eMovementTypeStand) ||
 		path().empty() ||
 		(path().size() <= detail().curr_travel_point_index()) ||