GH-131238: Core header refactor (GH-131250)

* Moves most structs in pycore_ header files into pycore_structs.h and pycore_runtime_structs.h

* Removes many cross-header dependencies

Objects/genobject.c

@@ -3,6 +3,8 @@
 #define _PY_INTERPRETER
 
 #include "Python.h"
+#include "pycore_genobject.h"
+
 #include "pycore_call.h"          // _PyObject_CallNoArgs()
 #include "pycore_ceval.h"         // _PyEval_EvalFrame()
 #include "pycore_frame.h"         // _PyInterpreterFrame

Objects/listobject.c

@@ -13,6 +13,7 @@
 #include "pycore_modsupport.h"    // _PyArg_NoKwnames()
 #include "pycore_object.h"        // _PyObject_GC_TRACK(), _PyDebugAllocatorStats()
 #include "pycore_tuple.h"         // _PyTuple_FromArray()
+#include "pycore_typeobject.h"    // _Py_TYPE_VERSION_LIST
 #include "pycore_setobject.h"     // _PySet_NextEntry()
 #include <stddef.h>
 

Objects/object.c

@@ -14,6 +14,7 @@
 #include "pycore_initconfig.h"    // _PyStatus_EXCEPTION()
 #include "pycore_instruction_sequence.h" // _PyInstructionSequence_Type
 #include "pycore_hashtable.h"     // _Py_hashtable_new()
+#include "pycore_hamt.h"          // _PyHamtItems_Type
 #include "pycore_memoryobject.h"  // _PyManagedBuffer_Type
 #include "pycore_namespace.h"     // _PyNamespace_Type
 #include "pycore_object.h"        // PyAPI_DATA() _Py_SwappedOp definition

Objects/unicodeobject.c

@@ -53,6 +53,7 @@ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 #include "pycore_object.h"        // _PyObject_GC_TRACK(), _Py_FatalRefcountError()
 #include "pycore_pathconfig.h"    // _Py_DumpPathConfig()
 #include "pycore_pyerrors.h"      // _PyUnicodeTranslateError_Create()
+#include "pycore_pyhash.h"        // _Py_HashSecret_t
 #include "pycore_pylifecycle.h"   // _Py_SetFileSystemEncoding()
 #include "pycore_pystate.h"       // _PyInterpreterState_GET()
 #include "pycore_ucnhash.h"       // _PyUnicode_Name_CAPI