NpcVisual:
- Add navigation_failed(sim_id) signal distinct from arrived_at_target
so the simulation layer can distinguish genuine arrival from failure
- Replace integer stuck_counter with delta-based stuck_time and
exported stuck_timeout (1.5s) for frame-rate-independent detection
- Add path_request_id / path_pending mechanism to reject stale
async path results when a new target is set or NPC dies
- On empty path or stuck movement, emit navigation_failed instead
of arriving; only emit arrived_at_target when truly close to target
- Reduce arrival_distance back to 0.6 now that navigation_failure
is properly signalled (no longer needed as a workaround)
- clamp arrival_distance reference in apply_dead_visual_state
SimNPC:
- Remove retry_count (replaced by navigation_failed signal pathway)
- Move last_task assignment from set_task() to task completion in
SimulationManager so it reflects the task that actually finished
SimulationManager:
- Add notify_npc_navigation_failed(): release reservation, record
last_task, send NPC to wander for 2s, emit task_changed signal
- Add notify_npc_target_unavailable() as public alias of above
- Guard extraction with node.reserved_by == npc.id to prevent
stale/illegitimate extraction when reservation is lost
- Guard fallback zone task completion (apply_npc_task) so it only
fires for non-resource tasks (gather_food/wood with no target
silently skip instead of applying zone values)
- Remove retry_count safety net (fully replaced by signal pipeline)
WorldViewManager:
- Connect navigation_failed signal in spawn_npc_visual()
- Skip target assignment for empty/idle/dead task states
- When no resource node available for gather_food/wood, call
notify_npc_target_unavailable() so NPC wanders instead of idling
- Add _on_npc_visual_navigation_failed handler delegating to
SimulationManager.notify_npc_navigation_failed()
- Remove retry_count references