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/Include/sliceobject.h

@@ -0,0 +1,50 @@
+#ifndef Py_SLICEOBJECT_H
+#define Py_SLICEOBJECT_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* The unique ellipsis object "..." */
+
+PyAPI_DATA(PyObject) _Py_EllipsisObject; /* Don't use this directly */
+
+#define Py_Ellipsis (&_Py_EllipsisObject)
+
+/* Slice object interface */
+
+/*
+
+A slice object containing start, stop, and step data members (the
+names are from range).  After much talk with Guido, it was decided to
+let these be any arbitrary python type.  Py_None stands for omitted values.
+*/
+
+typedef struct {
+    PyObject_HEAD
+    PyObject *start, *stop, *step;	/* not NULL */
+} PySliceObject;
+
+PyAPI_DATA(PyTypeObject) PySlice_Type;
+PyAPI_DATA(PyTypeObject) PyEllipsis_Type;
+
+#define PySlice_Check(op) (Py_TYPE(op) == &PySlice_Type)
+
+PyAPI_FUNC(PyObject *) PySlice_New(PyObject* start, PyObject* stop,
+                                  PyObject* step);
+PyAPI_FUNC(PyObject *) _PySlice_FromIndices(Py_ssize_t start, Py_ssize_t stop);
+PyAPI_FUNC(int) PySlice_GetIndices(PySliceObject *r, Py_ssize_t length,
+                                  Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step);
+PyAPI_FUNC(int) PySlice_GetIndicesEx(PySliceObject *r, Py_ssize_t length,
+				    Py_ssize_t *start, Py_ssize_t *stop, 
+				    Py_ssize_t *step, Py_ssize_t *slicelength);
+
+PyAPI_FUNC(int) _PySlice_Unpack(PyObject *slice,
+                                Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step);
+PyAPI_FUNC(Py_ssize_t) _PySlice_AdjustIndices(Py_ssize_t length,
+                                              Py_ssize_t *start, Py_ssize_t *stop,
+                                              Py_ssize_t step);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* !Py_SLICEOBJECT_H */