ci: migrate to uv! (#4698)

* Migrate to `uv`
* Format `pyproject.toml` files properly
* Remove upper bounds on dependencies, and bounds on dev dependencies
(we should be using latest)
* Move to hatch for packaing

In the future we should:
* Set up dependabot / automate lockfile updates and tests
* Add tests for min compatible versions (I'll do this right after merge)
* Use dynamic versioning
* Bump `pydantic` to v2.11.4 in the lockfile, we have some tests failing

libs/cli/langgraph_cli/cli.py

@@ -4,7 +4,8 @@ import os
 import pathlib
 import shutil
 import sys
-from typing import Callable, List, Optional, Sequence, Tuple
+from collections.abc import Sequence
+from typing import Callable, Optional
 
 import click
 import click.exceptions
@@ -741,7 +742,7 @@ def prepare_args_and_stdin(
     image: Optional[str] = None,
     # Like "langchain/langgraphjs-api" or "langchain/langgraph-api
     base_image: Optional[str] = None,
-) -> Tuple[List[str], str]:
+) -> tuple[list[str], str]:
     assert config_path.exists(), f"Config file not found: {config_path}"
     # prepare args
     stdin = langgraph_cli.docker.compose(
@@ -787,7 +788,7 @@ def prepare(
     postgres_uri: Optional[str] = None,
     image: Optional[str] = None,
     base_image: Optional[str] = None,
-) -> Tuple[List[str], str]:
+) -> tuple[list[str], str]:
     """Prepare the arguments and stdin for running the LangGraph API server."""
     config_json = langgraph_cli.config.validate_config_file(config_path)
     # pull latest images