feat: add Python/Rust SDK (appkit-rs) and Python app template #4

Job	Run time
Rust tests	4s
Build wheels (aarch64-unknown-linux-gnu)	3s
Build wheels (x86_64-unknown-linux-gnu)	4s
Python tests	4s
Build wheels (aarch64-apple-darwin)	1d 0h 0m 0s
Build wheels (x86_64-apple-darwin)	1d 0h 0m 0s
Generate SHA256	0s
Smoke test	0s
Publish to PyPI	0s
	2d 0h 0m 15s

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