Add DAT finale flow, editor, and new soundtrack assets

README.md

@@ -241,6 +241,24 @@ Units interact through a centralized collision and event system:
     - `numpy` 2.3.4 for vectorized collision detection
     - `sdl2` for graphics and window management
 
+## Map Editor
+
+The project now includes a Tkinter editor for `level.dat` archives:
+
+- Launch with `python tools/level_editor.py`
+- Open a specific archive with `python tools/level_editor.py --file assets/Rat/level.dat`
+- Start on a specific level with `python tools/level_editor.py --file assets/Rat/level.dat --level 7`
+- The editor requires a Python installation with the standard `tkinter` module available at OS level
+
+Editor capabilities:
+
+- Edits the full 32-level DAT archive used by the game
+- Creates new DAT archives with 32 default levels
+- Paints `EMPTY`, `WALL`, and `TUNNEL` tiles with brush, fill, and rectangle tools
+- Supports undo/redo, level copy/paste, and level duplication between slots
+- Imports a single level from JSON and exports the current level back to JSON
+- Validates common gameplay issues such as missing spawn cells, open borders, and disconnected traversable areas
+
 ## Level Sources
 
 - Preferred source: `assets/Rat/level.dat`