[PATCH] load.c: Fix dest and src of MEMMOVE

	When multiple files with the same name are required, the features_index
	hash stores the indexes in `$LOADED_FEATURES` array into a darray.
	The dest and src arguments for `MEMMOVE` were wrongly reversed when
	inserting a new index in the darray.

	[Bug #21568]

Our cgit server has been shut down.

tool/merger.rb: Fetch a diff in the patch format

It expects "Subject:", so it needs to be a patch file.

https://github.blog/changelog/2025-09-19-github-actions-macos-13-runner-image-is-closing-down/

This reverts commit c414b9871f263331cde0af1c08cf5c1a47e1aedf.

This reverts commit 4306c9048fb674d24b92dc46b6746a4749564147.

	IBF: Avoid unaligned load on 32 bit platforms

	[Bug #21569]

	Properly unlock locked mutexes on thread cleanup.

	Mutexes were being improperly unlocked on thread cleanup. This bug was
	introduced in 050a8954395.

	We must keep a reference from the mutex to the thread, because if the fiber
	is collected before the mutex is, then we cannot unlink it from the thread in
	`mutex_free`. If it's not unlinked from the the thread when it's freed, it
	causes bugs in `rb_thread_unlock_all_locking_mutexes`.

	We now mark the fiber when a mutex is locked, and the thread is marked
	as well. However, a fiber can still be freed in the same GC cycle as the
	mutex, so the reference to the thread is still needed.

	The reason we need to mark the fiber is that `mutex_owned_p()` has an ABA
	issue where if the fiber is collected while it's locked, a new fiber could be
	allocated at the same memory address and we could get false positives.

	Fixes [Bug #21342]

	Co-authored-by: John Hawthorn <john@hawthorn.email>