- Rewritten native API methods for embeddings to return pointers - null is a valid value for these methods to return so `Span` is not appropriate

* Embeddings correction

* Updated binaries, using [this build](https://github.com/SciSharp/LLamaSharp/actions/runs/8654672719/job/23733195669) for llama.cpp commit `f7001ccc5aa359fcf41bba19d1c99c3d25c9bcc7`.

 - Added all new functions.
 - Moved some functions (e.g. `SafeLlamaModelHandle` specific functions) into `SafeLlamaModelHandle.cs`
 - Exposed tokens on `SafeLlamaModelHandle` and `LLamaWeights` through a `Tokens` property. As new special tokens are added in the future they can be added here.
 - Changed all token properties to return nullable tokens, to handle some models not having some tokens.
 - Fixed `DefaultSamplingPipeline` to handle no newline token in some models.

* Moved native methods to more specific locations.

 - Context specific things have been moved into `SafeLLamaContextHandle.cs` and made private - they're exposed through C# properties and methods already.
 - Checking that GPU layer count is zero if GPU offload is not supported.
 - Moved methods for creating default structs (`llama_model_quantize_default_params` and `llama_context_default_params`) into relevant structs.

* Removed exception if `GpuLayerCount > 0` when GPU is not supported.

* - Added low level wrapper methods for new per-sequence state load/save in `SafeLLamaContextHandle`
 - Added high level wrapper methods (save/load with `State` object or memory mapped file) in `LLamaContext`
 - Moved native methods for per-sequence state load/save into `SafeLLamaContextHandle`

* Added update and defrag methods for KV cache in `SafeLLamaContextHandle`

* Updated submodule to `f7001ccc5aa359fcf41bba19d1c99c3d25c9bcc7`

* Passing the sequence ID when saving a single sequence state

- Modified `GetEmbeddings` method to be async

- Added a `DecodeAsync` overload which runs the work in a task
 - Replaced some `NativeHandle` usage in `BatchedDecoding` with higher level equivalents.
 - Made the `LLamaBatch` grow when token capacity is exceeded, removing the need to manage token capacity externally.

- Wrapped some native functions which take (pointer, length) in function which take a `span` instead.

- Made `NativeApi` into a `static class` (it's not intended to be instantiated)
 - Moved `LLamaTokenType` enum out into a separate file
 - Made `LLamaSeqId` and `LLamaPos` into `record struct`, convenient to have equality etc

- params contains a list of loras, instead of just one

Add GGUF support

- Used those methods to add a `Clone` method to SafeLLamaContextHandle
 - Simplified `LLamaContext` by using the new methods
 - Sealed `LLamaContext` and `LLamaEmbedder`

- Also refactored it to return an `int[]` instead of an `IEnumerable<int>`, solving the "multiple enumeration" problems at the source!