fix: use signal/slot for thread-safe GUI updates

- Add refresh_needed signal to HUDOverlay
- Connect signal to _refresh_display with QueuedConnection
- Update all update methods to emit signal instead of calling _refresh_display directly
- This ensures all GUI operations (setStyleSheet, setText) happen on main thread
- Fixes crash caused by GUI operations from LogWatcher thread

ui/hud_overlay_clean.py

@@ -295,6 +295,7 @@ class HUDOverlay(QWidget):
 
     position_changed = pyqtSignal(QPoint)
     stats_updated = pyqtSignal(dict)
+    refresh_needed = pyqtSignal()  # Signal to trigger refresh on main thread
 
     def __init__(self, parent=None, config_path: Optional[str] = None):
         super().__init__(parent)
@@ -323,6 +324,9 @@ class HUDOverlay(QWidget):
         self._timer = QTimer(self)
         self._timer.timeout.connect(self._update_session_time)
 
+        # Connect refresh signal to ensure GUI updates happen on main thread
+        self.refresh_needed.connect(self._refresh_display, Qt.ConnectionType.QueuedConnection)
+
     def _load_hud_config(self) -> HUDConfig:
         """Load HUD configuration."""
         try:
@@ -883,7 +887,8 @@ class HUDOverlay(QWidget):
                 self._stats.loot_other += value_ped
 
             self._stats.recalculate()
-            self._refresh_display()
+            # Emit signal to refresh on main thread instead of calling directly
+            self.refresh_needed.emit()
             logger.debug(f"[HUD] update_loot complete: shrapnel={self._stats.shrapnel_total}, other={self._stats.loot_other}")
 
     def update_shrapnel(self, amount: Decimal):
@@ -897,7 +902,7 @@ class HUDOverlay(QWidget):
             self._stats.weapon_cost_total += cost_ped
             self._stats.cost_total += cost_ped
             self._stats.recalculate()
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def update_armor_cost(self, cost_ped: Decimal):
         """Update armor cost."""
@@ -906,7 +911,7 @@ class HUDOverlay(QWidget):
             self._stats.armor_cost_total += cost_ped
             self._stats.cost_total += cost_ped
             self._stats.recalculate()
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def update_healing_cost(self, cost_ped: Decimal):
         """Update healing cost."""
@@ -915,14 +920,14 @@ class HUDOverlay(QWidget):
             self._stats.healing_cost_total += cost_ped
             self._stats.cost_total += cost_ped
             self._stats.recalculate()
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def update_kills(self, count: int = 1):
         """Update kill count."""
         logger.debug(f"[HUD] update_kills called: count={count}, session_active={self.session_active}")
         if self.session_active:
             self._stats.kills += count
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def update_skill(self, skill_name: str, amount: Decimal):
         """Update skill gain tracking."""
@@ -934,13 +939,13 @@ class HUDOverlay(QWidget):
             self._stats.skill_gains[skill_name] += amount
             # Update total
             self._stats.total_skill_gained += amount
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def update_globals(self):
         """Update global count."""
         if self.session_active:
             self._stats.globals_count += 1
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def update_damage(self, dealt: Decimal = Decimal('0'), taken: Decimal = Decimal('0')):
         """Update damage stats."""
@@ -949,7 +954,7 @@ class HUDOverlay(QWidget):
                 self._stats.damage_dealt += dealt
             if taken > 0:
                 self._stats.damage_taken += taken
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     # === Event Handlers for LogWatcher ===
 
@@ -957,20 +962,20 @@ class HUDOverlay(QWidget):
         """Handle global event from LogWatcher."""
         if self.session_active:
             self._stats.globals_count += 1
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def on_hof(self, value_ped=Decimal('0.0')):
         """Handle Hall of Fame event from LogWatcher."""
         if self.session_active:
             self._stats.hofs_count += 1
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def on_personal_global(self, value_ped=Decimal('0.0')):
         """Handle personal global event from LogWatcher."""
         # Only count personal globals, not all globals
         if self.session_active:
             self._stats.globals_count += 1
-            self._refresh_display()
+            self.refresh_needed.emit()
 
     def on_damage_dealt(self, damage):
         """Handle damage dealt event from LogWatcher."""