Update keybindings and enhance loading screen functionality

- Refactor keybindings for gas spawning across multiple configurations
- Implement new loading screen updates during game initialization
- Add tests to ensure all weapon actions are exposed in keybinding profiles
- Introduce new assets for explosion effects

engine/graphics.py

@@ -9,6 +9,12 @@ class Graphics():
     def load_assets(self):
         theme_index = self.get_theme_index()
         print(f"[gfx] load_assets requested: level={self.current_level + 1} theme={theme_index}")
+        if getattr(self, "startup_loading_active", False):
+            self._update_startup_loading(
+                "Loading graphics",
+                detail=f"Preparing theme {theme_index}",
+                progress=0.3,
+            )
         if not hasattr(self, "theme_assets_cache"):
             self.theme_assets_cache = {}
         if not hasattr(self, "blood_layer_sprites"):
@@ -18,6 +24,12 @@ class Graphics():
 
         if not getattr(self, "common_assets_loaded", False):
             print("Loading graphics assets...")
+            if getattr(self, "startup_loading_active", False):
+                self._update_startup_loading(
+                    "Loading graphics",
+                    detail="Decoding sprites and tiles",
+                    progress=0.4,
+                )
             self.rat_assets = {}
             self.rat_assets_textures = {}
             self.rat_image_sizes = {}
@@ -56,6 +68,12 @@ class Graphics():
                     )
 
             print("Pre-generating blood stain pool...")
+            if getattr(self, "startup_loading_active", False):
+                self._update_startup_loading(
+                    "Loading graphics",
+                    detail="Generating blood pool",
+                    progress=0.58,
+                )
             self.blood_stain_textures = []
             for _ in range(10):
                 blood_surface = self.render_engine.generate_blood_surface()
@@ -70,6 +88,12 @@ class Graphics():
 
         if theme_index not in self.theme_assets_cache:
             print(f"Loading theme assets {theme_index}...")
+            if getattr(self, "startup_loading_active", False):
+                self._update_startup_loading(
+                    "Loading graphics",
+                    detail=f"Loading theme {theme_index} art",
+                    progress=0.74,
+                )
             self.theme_assets_cache[theme_index] = {
                 "floor_tile": self.render_engine.create_color_surface((128, 128, 128)),
                 "tunnel": self.render_engine.load_image("Rat/BMP_TUNNEL.png"),
@@ -122,6 +146,13 @@ class Graphics():
         else:
             print(f"[gfx] theme cache hit -> reusing theme {theme_index}")
 
+        if getattr(self, "startup_loading_active", False):
+            self._update_startup_loading(
+                "Loading graphics",
+                detail="Finishing render setup",
+                progress=0.84,
+            )
+
         self.loaded_theme_index = theme_index
         theme_assets = self.theme_assets_cache[theme_index]
         self.floor_tile = theme_assets["floor_tile"]