feat: connect loadout selection to session cost tracking

- start_session now uses _session_loadout_name for HUD display
- Added _setup_session_cost_tracker to initialize SessionCostTracker
- Added _on_cost_update callback to update HUD with live costs
- Loadout name now appears in HUD instead of 'Default'

ui/main_window.py

@@ -940,13 +940,22 @@ class MainWindow(QMainWindow):
         weapon_dpp = Decimal(str(weapon_stats.get('dpp', 0)))
         weapon_cost_per_hour = Decimal(str(weapon_stats.get('cost_per_hour', 0)))
 
+        # Get loadout name from session selection
+        loadout_name = getattr(self, '_session_loadout_name', None) or "Default"
+        loadout_id = getattr(self, '_session_loadout_id', None)
+
         self.hud.start_session(
             weapon=weapon_name,
-            loadout="Default",
+            loadout=loadout_name,
             weapon_dpp=weapon_dpp,
             weapon_cost_per_hour=weapon_cost_per_hour
         )
-        self.log_info("HUD", f"HUD shown - Weapon: {weapon_name} (DPP: {weapon_dpp:.2f}, Cost/h: {weapon_cost_per_hour:.2f} PED)")
+
+        # Set up cost tracker if loadout selected
+        if loadout_id:
+            self._setup_session_cost_tracker(loadout_id)
+
+        self.log_info("HUD", f"HUD shown - Weapon: {weapon_name}, Loadout: {loadout_name} (DPP: {weapon_dpp:.2f}, Cost/h: {weapon_cost_per_hour:.2f} PED)")
 
     def _setup_log_watcher_callbacks(self):
         """Setup LogWatcher event callbacks."""
@@ -1136,6 +1145,40 @@ class MainWindow(QMainWindow):
             self._log_watcher_thread = None
             self.log_info("LogWatcher", "Stopped")
 
+    def _setup_session_cost_tracker(self, loadout_id: int):
+        """Set up session cost tracker with selected loadout."""
+        from core.session_cost_tracker import SessionCostTracker
+        from core.database import DatabaseManager
+        
+        try:
+            db = DatabaseManager()
+            self._cost_tracker = SessionCostTracker(
+                session_id=self._current_db_session_id,
+                loadout_id=loadout_id,
+                db_manager=db
+            )
+            self._cost_tracker.register_callback(self._on_cost_update)
+            self.log_info("CostTracker", f"Cost tracking enabled for loadout ID: {loadout_id}")
+        except Exception as e:
+            self.log_error("CostTracker", f"Failed to set up cost tracker: {e}")
+    
+    def _on_cost_update(self, state):
+        """Handle cost update from SessionCostTracker."""
+        # Update HUD with new cost state
+        if hasattr(self, 'hud') and self.hud:
+            summary = {
+                'weapon_cost': state.weapon_cost,
+                'armor_cost': state.armor_cost,
+                'healing_cost': state.healing_cost,
+                'enhancer_cost': state.enhancer_cost,
+                'mindforce_cost': state.mindforce_cost,
+                'shots_fired': state.shots_fired,
+                'hits_taken': state.hits_taken,
+                'heals_used': state.heals_used,
+            }
+            self.hud._stats.update_from_cost_tracker(summary)
+            self.hud._refresh_display()
+
     def _process_queued_events(self):
         """Process events from the queue in the main thread (SQLite thread safety)."""
         from core.project_manager import LootEvent