ggml/gguf : prevent integer overflows (#19856)
* gguf : prevent integer overflow for ggml_context mem size
* ggml : fix int overflows in ggml_new_object()
* gguf : prevent string exhaustion
* gguf : prevent array elements exhaustion
* ggml : fix negative tensor type oob
* py : assert that alignment is non-zero power of 2
* ggml : check int overflow in ggml_new_tensor_impl and ggml_new_object
* gguf-py : error on duplicate keys when reading
* py : restore tensor_fields
* enforce proper alignment in add_custom_alignment
* gguf : better name
* gguf : fix ctx size for no_alloc == true
* gguf : minor print fix
* ggml : print values when overflow
* ggml : remove deprecated ggml_type_sizef()
* ggml : relax ggml_type asserts to debug-only
* gguf : add mem_size overflow test
* gguf : add file size check for arrays
* ggml : relax asseerts for ggml_get_type_traits()
* flake8 fix
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Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>
