Debug view improvements, warp animation

* Add a visible frame one tile beyond the normal screen in debug mode.

* Fix the display of motion paths for mounted traps in debug mode.

* Add an animation for the warp trap.

game/game.py

@@ -35,8 +35,10 @@ class Game:
 
         # Size the window ONCE to fit the largest level, then never resize it —
         # calling set_mode again mid-session recreates the window (it flickers /
-        # looks like it closes). Smaller levels are centred within it.
-        dims = [(lv.width, lv.height) for lv in map(Level, self.level_paths)]
+        # looks like it closes). Smaller levels are centred within it. The debug
+        # view reveals a margin of overscan around a level, so budget for it here
+        # (for any level that will be shown in debug) or it'd be clipped.
+        dims = [self._draw_size(lv) for lv in map(Level, self.level_paths)]
         self.win_w = max(max(w for w, _ in dims), MIN_W)
         self.win_h = max(h for _, h in dims) + HUD_H
         self.screen = pygame.display.set_mode((self.win_w, self.win_h))
@@ -44,16 +46,34 @@ class Game:
         self._load_current()
 
     # --- level management ----------------------------------------------------
+    def _debug_margin(self, level):
+        """Pixels of overscan drawn around a level in the debug view (0 if it
+        won't be shown in debug)."""
+        if not (self.force_debug or level.debug):
+            return 0
+        return S.DEBUG_VIEW_MARGIN * level.tile
+
+    def _draw_size(self, level):
+        """The pixel size the level's play surface occupies, including any debug
+        overscan margin on both sides."""
+        m = self._debug_margin(level)
+        return level.width + 2 * m, level.height + 2 * m
+
     def _load_current(self):
         self.level = Level(self.level_paths[self.index])
         if self.force_debug:
             self.level.debug = True   # CLI flag overrides the per-level setting
         self.player = Player(self.level)
         self.battery = self.level.battery
-        self.world = pygame.Surface((self.level.width, self.level.height))
+        # In debug, grow the play surface by a margin and shift all drawing into
+        # it (render_offset) so geometry just off the map is visible.
+        m = self._debug_margin(self.level)
+        self.level.render_offset = (m, m)
+        world_w, world_h = self._draw_size(self.level)
+        self.world = pygame.Surface((world_w, world_h))
         # Centre the play area in the fixed window, below the HUD.
-        ox = (self.win_w - self.level.width) // 2
-        oy = HUD_H + (self.win_h - HUD_H - self.level.height) // 2
+        ox = (self.win_w - world_w) // 2
+        oy = HUD_H + (self.win_h - HUD_H - world_h) // 2
         self.world_pos = (ox, oy)
         self.state = "playing"
         self.death_timer = 0.0
@@ -238,7 +258,7 @@ class Game:
             # The traps stay drawn in their moment-of-death state; the player is
             # replaced by a corpse sprite where they fell.
             sprite = self.assets.get("player_dead", self.death_rect.w, self.death_rect.h)
-            self.world.blit(sprite, self.death_rect)
+            self.world.blit(sprite, self.death_rect.move(self.level.render_offset))
         else:
             self.player.draw(self.world, self.assets)