some engineering refactors

[thxCode]

This PR is going to refactor/introduce the following changes.

• .gitignore: ignore cmake-* and .idea dirs.
• Align the ggml backend (s/CUBLAS/CUDA/g, s/HIPBLAS/HIP/g) and support CANN, MUSA.
• Extract public utils for reusing sampler_method/scheduler/rng.
• Support specifying main-gpu at the API level.
• Migrate sd_type_t to ggml_type.

[Green-Sky]

Generally agree with this stuff. :)

[leejet]

stable-diffusion.h is a standalone header file and should not depend on ggml.h. When sd.cpp is provided as a third-party library, user only need to use stable-diffusion.h and the corresponding library files.

[thxCode]

stable-diffusion.h is a standalone header file and should not depend on ggml.h. When sd.cpp is provided as a third-party library, user only need to use stable-diffusion.h and the corresponding library files.

rebase master and revert the change, PTAL.

[newfla]

Amazing work, the pr fixes broken Rocm and Metal backends 👏