Fix Windows shared memory segment cleanup in shmctl IPC_RMID

Add proper handle cleanup when marking shared memory segment for deletion.
Previously, shmctl(IPC_RMID) only marked the segment by setting key to -1
but did not close the Windows file mapping handle, causing the segment to
persist in the system.

This led to errors when trying to reopen segments with the same key:
- Segment remained accessible via OpenFileMapping()
- But had key = -1, failing validation checks
- Resulted in "Invalid argument" errors

Now properly closes the handle, allowing Windows to destroy the named
mapping object when no processes are attached, matching POSIX semantics
where IPC_RMID marks segment for deletion.

Fixes issue where shmop_open() with 'c' flag fails after shmop_delete().

Author: EdmondDantes

TSRM/tsrm_win32.c

@@ -823,6 +823,11 @@ TSRM_API int shmctl(int key, int cmd, struct shmid_ds *buf)
 		case IPC_RMID:
 			if (shm->descriptor->shm_nattch < 1) {
 				shm->descriptor->shm_perm.key = -1;
+				/* Close handle to allow Windows to destroy the named mapping object */
+				if (shm->segment && shm->segment != INVALID_HANDLE_VALUE) {
+					CloseHandle(shm->segment);
+					shm->segment = INVALID_HANDLE_VALUE;
+				}
 			}
 			return 0;