gh-117953: Track Extra Details in Global Extensions Cache (gh-118532)

We have only been tracking each module's PyModuleDef.  However, there are some problems with that.  For example, in some cases we load single-phase init extension modules from def->m_base.m_init or def->m_base.m_copy, but if multiple modules share a def then we can end up with unexpected behavior.

With this change, we track the following:

* PyModuleDef (same as before)
* for some modules, its init function or a copy of its __dict__, but specific to that module
* whether it is a builtin/core module or a "dynamic" extension
* the interpreter (ID) that owns the cached __dict__ (only if cached)

This also makes it easier to remember the module's kind (e.g. single-phase init) and if loading it previously failed, which I'm doing separately.

Include/internal/pycore_importdl.h

@@ -22,6 +22,11 @@ typedef enum ext_module_kind {
  _Py_ext_module_kind_INVALID = 3,
 } _Py_ext_module_kind;
 
+typedef enum ext_module_origin {
+ _Py_ext_module_origin_CORE = 1,
+ _Py_ext_module_origin_BUILTIN = 2,
+ _Py_ext_module_origin_DYNAMIC = 3,
+} _Py_ext_module_origin;
 
 /* Input for loading an extension module. */
 struct _Py_ext_module_loader_info {
@@ -34,6 +39,7 @@ struct _Py_ext_module_loader_info {
  /* path is always a borrowed ref of name or filename,
  * depending on if it's builtin or not. */
  PyObject *path;
+ _Py_ext_module_origin origin;
  const char *hook_prefix;
  const char *newcontext;
 };
@@ -42,7 +48,11 @@ extern void _Py_ext_module_loader_info_clear(
 extern int _Py_ext_module_loader_info_init(
  struct _Py_ext_module_loader_info *info,
  PyObject *name,
- PyObject *filename);
+ PyObject *filename,
+ _Py_ext_module_origin origin);
+extern int _Py_ext_module_loader_info_init_for_core(
+ struct _Py_ext_module_loader_info *p_info,
+ PyObject *name);
 extern int _Py_ext_module_loader_info_init_for_builtin(
  struct _Py_ext_module_loader_info *p_info,
  PyObject *name);