feat: quivr core minimal chat (#2818)

# Description
- Introduce `LLMEndpoint` class: wrapper around a `BaseChatLLM` to load
OpenAI compatible models
- Add `brain.search(...)` function to retrieve
- Test with test-coverage: 
- Added ability to load brain `from langchain.Document`
- Configured mypy and poetry lock in `.pre-commit.yaml`

# Test coverage

![image](https://github.com/QuivrHQ/quivr/assets/14312141/629ede66-146e-400f-b40b-8c22a9258a47)

---------

Co-authored-by: aminediro <aminedirhoussi@gmail.com>

backend/.pre-commit-config.yaml

@@ -22,3 +22,19 @@ repos:
         args: [--fix]
       # Run the formatter.
       - id: ruff-format
+  - repo: https://github.com/pre-commit/mirrors-mypy
+    rev: v1.10.0
+    hooks:
+      - id: mypy
+        name: mypy
+        additional_dependencies: ["types-aiofiles"]
+
+  - repo: https://github.com/python-poetry/poetry
+    rev: "" # add version here
+    hooks:
+      - id: poetry-check
+        args: ["-C", "./backend/core"]
+      - id: poetry-lock
+        args: ["-C", "./backend/core"]
+      - id: poetry-install
+        args: ["-C", "./backend/core"]

backend/core/pyproject.toml

@@ -33,6 +33,7 @@ pytest-cov = "^5.0.0"
 [tool.poetry.group.test.dependencies]
 pytest-asyncio = "^0.23.7"
 pytest = "^8.2.2"
+pytest-xdist = "^3.6.1"
 
 
 [tool.mypy]