layout: restructure into src/ tests/ android/ scripts/ tools/

- extension/src/{port,platform,codepage} -> src/; native_render -> src/host
  (+ dxt, shaders/); libgr2 -> src/gr2; extension/third_party -> third_party
- extension/tests -> tests/port, libgr2/tests -> tests/gr2
- android-native -> android (build.sh, push-client.sh moved in)
- script -> scripts; tools/40250 -> tools/server; oracle -> tools/granny-oracle;
  perf tools -> tools/perf
- all build trees under build/ (native, release, android, port-gate)
- xrender:: CMake aliases -> mt::; port-map ledger impl paths rewritten

No code changes. ctest 15/15, port_gate macos+android PASS, port_map check 0 errors.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

third_party/cpython-2.7.18/Python/importdl.h

@@ -0,0 +1,53 @@
+#ifndef Py_IMPORTDL_H
+#define Py_IMPORTDL_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* Definitions for dynamic loading of extension modules */
+enum filetype {
+    SEARCH_ERROR,
+    PY_SOURCE,
+    PY_COMPILED,
+    C_EXTENSION,
+    PY_RESOURCE, /* Mac only */
+    PKG_DIRECTORY,
+    C_BUILTIN,
+    PY_FROZEN,
+    PY_CODERESOURCE, /* Mac only */
+    IMP_HOOK
+};
+
+struct filedescr {
+    char *suffix;
+    char *mode;
+    enum filetype type;
+};
+extern struct filedescr * _PyImport_Filetab;
+extern const struct filedescr _PyImport_DynLoadFiletab[];
+
+extern PyObject *_PyImport_LoadDynamicModule(char *name, char *pathname,
+                                             FILE *);
+
+/* Max length of module suffix searched for -- accommodates "module.slb" */
+#define MAXSUFFIXSIZE 12
+
+#ifdef MS_WINDOWS
+#include <windows.h>
+typedef FARPROC dl_funcptr;
+#else
+#if defined(PYOS_OS2) && !defined(PYCC_GCC)
+#include <os2def.h>
+typedef int (* APIENTRY dl_funcptr)();
+#else
+typedef void (*dl_funcptr)(void);
+#endif
+#endif
+
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* !Py_IMPORTDL_H */