WASM Python integration milestone - game.py runs in browser

Major milestone for issue #158 (Emscripten/WebAssembly build target):
- Python 3.14 successfully initializes and runs in WASM
- mcrfpy module loads and works correctly
- Game scripts execute with full level generation
- Entities (boulders, rats, cyclops, spawn points) placed correctly

Key changes:
- CMakeLists.txt: Add 2MB stack, Emscripten link options, preload files
- platform.h: Add WASM-specific implementations for executable paths
- HeadlessTypes.h: Make Texture/Font/Sound stubs return success
- CommandLineParser.cpp: Guard filesystem operations for WASM
- McRFPy_API.cpp: Add WASM path configuration, debug output
- game.py: Make 'code' module import optional (not available in WASM)
- wasm_stdlib/: Add minimal Python stdlib for WASM (~4MB)

Build with: emmake make (from build-emscripten/)
Test with: node mcrogueface.js

Next steps:
- Integrate VRSFML for actual WebGL rendering
- Create HTML page to host WASM build
- Test in actual browsers

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/scripts/game.py

@@ -1,5 +1,8 @@
 import mcrfpy
-import code
+try:
+    import code
+except ImportError:
+    code = None  # Interactive console not available in WASM
 
 #t = mcrfpy.Texture("assets/kenney_tinydungeon.png", 16, 16) # 12, 11)
 t = mcrfpy.Texture("assets/kenney_TD_MR_IP.png", 16, 16) # 12, 11)
@@ -326,7 +329,8 @@ class Crypt:
         d = None
         if state == "end": return
         elif key == "Grave":
-            code.InteractiveConsole(locals=globals()).interact()
+            if code:  # Only available in native builds, not WASM
+                code.InteractiveConsole(locals=globals()).interact()
             return
         elif key == "Z":
             self.player.do_zap()