fix: compare next vs current occupancy counts instead of absolute threshold

Two entities on the same tile (16,-0.0) each saw count=2 and blocked each
other with occupied=true since 2>1. The collision check was treating the
entity's own presence as a blocker.

Now: only trigger avoidance when next_tile has strictly more entities than
current_tile. Handles path[0]=current_pos (count equal → move), two entities
passing through same tile (counts stay equal → move), and genuinely crowded
destinations (next has more → dodge). Also raise crowded threshold to 4+.

src/entities/shared_systems/pathfinding.rs

@@ -596,8 +596,10 @@ pub fn movement(
                 if ambulatory.path_index < path.len() {
                     let next_point = path[ambulatory.path_index];
 
-                    let current_crowded = occupancy.count_at(transform.translation) > 2;
-                    let occupied = !current_crowded && occupancy.count_at(next_point) > 1;
+                    let current_count = occupancy.count_at(transform.translation);
+                    let next_count = occupancy.count_at(next_point);
+                    let current_crowded = current_count > 3;
+                    let occupied = !current_crowded && next_count > current_count;
                     if occupied {
                         let move_dir = next_point - transform.translation;
                         if move_dir.length_squared() > 0.0 {