…ongh-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.

The assertion was added ingh-118532 but was based on the invalid assumption that PyState_FindModule() would only be called with an already-initialized module def.  I've added a test to make sure we don't make that assumption again.

…ongh-119561)The assertion was added inpythongh-118532 but was based on the invalid assumption that PyState_FindModule() would only be called with an already-initialized module def.  I've added a test to make sure we don't make that assumption again.(cherry picked from commit0c5ebe1)Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>

…119561) (gh-119632)The assertion was added ingh-118532 but was based on the invalid assumption that PyState_FindModule() would only be called with an already-initialized module def.  I've added a test to make sure we don't make that assumption again.(cherry picked from commit0c5ebe1)Co-authored-by: Eric Snow <ericsnowcurrently@gmail.com>

…ongh-119561)The assertion was added inpythongh-118532 but was based on the invalid assumption that PyState_FindModule() would only be called with an already-initialized module def.  I've added a test to make sure we don't make that assumption again.