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>

wasm_stdlib/lib/python3.14/_sitebuiltins.py

@@ -0,0 +1,103 @@
+"""
+The objects used by the site module to add custom builtins.
+"""
+
+# Those objects are almost immortal and they keep a reference to their module
+# globals.  Defining them in the site module would keep too many references
+# alive.
+# Note this means this module should also avoid keep things alive in its
+# globals.
+
+import sys
+
+class Quitter(object):
+    def __init__(self, name, eof):
+        self.name = name
+        self.eof = eof
+    def __repr__(self):
+        return 'Use %s() or %s to exit' % (self.name, self.eof)
+    def __call__(self, code=None):
+        # Shells like IDLE catch the SystemExit, but listen when their
+        # stdin wrapper is closed.
+        try:
+            sys.stdin.close()
+        except:
+            pass
+        raise SystemExit(code)
+
+
+class _Printer(object):
+    """interactive prompt objects for printing the license text, a list of
+    contributors and the copyright notice."""
+
+    MAXLINES = 23
+
+    def __init__(self, name, data, files=(), dirs=()):
+        import os
+        self.__name = name
+        self.__data = data
+        self.__lines = None
+        self.__filenames = [os.path.join(dir, filename)
+                            for dir in dirs
+                            for filename in files]
+
+    def __setup(self):
+        if self.__lines:
+            return
+        data = None
+        for filename in self.__filenames:
+            try:
+                with open(filename, encoding='utf-8') as fp:
+                    data = fp.read()
+                break
+            except OSError:
+                pass
+        if not data:
+            data = self.__data
+        self.__lines = data.split('\n')
+        self.__linecnt = len(self.__lines)
+
+    def __repr__(self):
+        self.__setup()
+        if len(self.__lines) <= self.MAXLINES:
+            return "\n".join(self.__lines)
+        else:
+            return "Type %s() to see the full %s text" % ((self.__name,)*2)
+
+    def __call__(self):
+        self.__setup()
+        prompt = 'Hit Return for more, or q (and Return) to quit: '
+        lineno = 0
+        while 1:
+            try:
+                for i in range(lineno, lineno + self.MAXLINES):
+                    print(self.__lines[i])
+            except IndexError:
+                break
+            else:
+                lineno += self.MAXLINES
+                key = None
+                while key is None:
+                    key = input(prompt)
+                    if key not in ('', 'q'):
+                        key = None
+                if key == 'q':
+                    break
+
+
+class _Helper(object):
+    """Define the builtin 'help'.
+
+    This is a wrapper around pydoc.help that provides a helpful message
+    when 'help' is typed at the Python interactive prompt.
+
+    Calling help() at the Python prompt starts an interactive help session.
+    Calling help(thing) prints help for the python object 'thing'.
+    """
+
+    def __repr__(self):
+        return "Type help() for interactive help, " \
+               "or help(object) for help about object."
+    def __call__(self, *args, **kwds):
+        import pydoc
+        return pydoc.help(*args, **kwds)