QOI support for IIP

[jerch]

Adds QOI support to the image addon.

Part of #5845.

Some benchmarks with https://github.com/jerch/sixel-bench (all my machine™ with Chromium):

Format	Protocol	TP in MB/s	FPS	VSCode MB/s	VSCode FPS	VSCode Penalty
Sixel	Sixel	39.46	227.92	5.8	33.48	6.8x
PNG	IIP	21.77	104.48	4.7	22.58	4.6x
JPEG	IIP	4.71	200.04	3.0	127.44	1.6x
QOI	IIP	43.78	229.31	-	-	-
PNG	Kitty	17.93	86.09	4.3	20.66	4.2x

Observation: QOI leads in throughput and FPS. Sixel is close behind but unusable for quick encoding and due its lower quality. The kitty implementation with PNG is worse than for IIP, prolly not as heavily optimized yet.

On a sidenote: Webkit/Safari is actually faster than Chromium yielding 2.82s (46.45 MB/s, 243.31 fps) for QOI. For Kitty it performs much worse with ~12 MB/s.

Edit: Added vscode numbers for comparison to xterm.js demo.

[jerch]

@Tyriar, @anthonykim1 This also removes the Image-load shim around missing createImageBitmap in older Safari (<16.4, fixed in Safari since March 27, 2023).

[jerch]

@Tyriar, @anthonykim1 Added numbers for vscode above in the table. Something in vscode terminal is sucking hard on the effective throughput, especially when the input is big (thus JPEG is less affected).

To repro yourself in vscode terminal:

git clone git@github.com:jerch/sixel-bench.git
cd sixel-bench
cat parts_* > blobs.tar.gz
tar -zxf blobs.tar.gz
reset
python run.py data/data.sixel
reset
python run.py data/data.iip.png

The reset is needed for the speed result numbers to show up. I don't know why it doesn't work without, seem the terminal tries to be smart about the prompt line?