llama : integer type consistency in `llama.h`

[MarcusDunn]

Feature Description

llama.h should prefer to use sized (always) + signed (mostly) integers.

Motivation

The integer types in llama.h right now are.

Count	Type
33	int
10	int32_t
24	uint32_t
2	int64_t
2	uint64_t

In #4540 there was a discussion around preferences for integer types on new methods.

Avoiding int makes cross platform code simpler at essentially no cost.
Signed makes arithmetic simpler at the cost of some bits if you need something large.

Possible Implementation

1. Change all int's to int32_t
2. As code changes try to prefer signed integers.

We could also do some higher-impact things, but I'd take the lower-impact slower changes over a large find-and-replace.

[ggerganov]

Nice, thanks for creating this

[LoganDark]

A bunch of things do not need to be signed, and a bunch of things that are int32s need to be size_ts instead. Using this library from Rust is a nightmare of constant integer casts that should be unnecessary because llama.cpp just arbitrary chooses types. I don't agree with this issue as-written but I do agree that the integer types in use are a mess and need to change. I'll take a quick look at your PR addressing this