externals: Update fmt to 8.0.0

[audout] Implement GetAudioOutPlayedSampleCount

Also removes some deprecated API usages.

maxwell3d: Add missing return in default SizeInBytes() case

We were returning '1' in ComponentCount()'s default case but were
neglecting to do the same with SizeInBytes().

GPU: Implement a garbage collector for GPU Caches (project Reaper+)

Keeps us up to date with the latest major release.

Also allows compilers that support it to perform compile-time format
string checking.

bootmanager: Use std::stop_source for stopping emulation

Simple resizing of Per-Game configuration window and removal of useless Help question mark button in the title bar

common/detached_tasks: Wait for tasks before shutting down

input_common/mouse_input: Fix data race

npad: Fix data race when updating devices

Simple resizing of the Per-Game configuration window and removal of useless Help question mark button in the title bar

common: fs: Miscellaneous changes

service: spl: Implement general SPL service

service: time: Use GetFileRelative to get files within subdirectories

This provides a more concrete example of what a regular file is and isn't.

These enforce requiring the file to exist prior to opening.

This check was preventing files with the Write or Append file access modes from being created, as per the documented behavior in FileAccessMode.
This amends the check to test for the existence of a filesystem object prior to checking whether it is a regular file.
Thanks to liushuyu for pointing out that removing the check altogether would not guard against attempting to open non-regular files such as directories, symlinks, FIFO (pipes), sockets, block devices, or character devices.
The documentation has also been updated for these functions to clarify that a file refers to a regular file.

Similarly, Flush() is typically called to attempt to flush a file into the disk. In the one case where this is used, we do not care whether the flush has succeeded or not, making [[nodiscard]] unnecessary.

There are a lot of scenarios where we don't particularly care whether or not the removal operation and just simply attempt a removal.

As such, removing the [[nodiscard]] attribute is best for these functions.

vk_master_semaphore: Use jthread for debug thread

ci: windows: Copy the Qt styles directory when packaging

core: Make is_powered_on atomic

Fixes potential data races when shutting down.

If this is not waited on, the synchronization primitives are destroyed
whe main exits and the detached task ends up signalling garbage and not
properly finishing.

Add a lock to avoid data races.
This reduces the number of -fsanitize=thread errors significantly.

Fix data race using std::jthread and std::stop_token.

kernel: Fix missing peak set in KResourceLimit::SetLimitValue

Used in Ninja Gaiden games.

Use its std::stop_token to abort shader cache loading.

Using std::stop_token instead of std::atomic_bool allows the usage of
other utilities like std::stop_callback.

Update dynarmic and add new unsafe CPU option.

nvflinger: Add experimental toggle to disable buffer swap interval limits

externals: httplib: replace custom httplib header with upstream as submodule