feat(settings): Update default model to TheBloke/Mistral-7B-Instruct-v0.2-GGUF (#1415)

* Update LlamaCPP dependency

* Default to TheBloke/Mistral-7B-Instruct-v0.2-GGUF

* Fix API docs

fern/docs/pages/api-reference/api-reference.mdx

@@ -1 +1,14 @@
 # API Reference
+
+The API is divided in two logical blocks:
+
+1. High-level API, abstracting all the complexity of a RAG (Retrieval Augmented Generation) pipeline implementation:
+    - Ingestion of documents: internally managing document parsing, splitting, metadata extraction,
+      embedding generation and storage.
+    - Chat & Completions using context from ingested documents: abstracting the retrieval of context, the prompt
+      engineering and the response generation.
+
+2. Low-level API, allowing advanced users to implement their own complex pipelines:
+    - Embeddings generation: based on a piece of text.
+    - Contextual chunks retrieval: given a query, returns the most relevant chunks of text from the ingested
+      documents.