Cornflow_client needs to have less restrictive dependencies

**Describe the bug**
When installing cornflow_client, I cannot use "recent" versions of pulp or pytups. Because it has upper limits to their version numbers.

**To Reproduce**
python -m pip install cornflow_client pytups pulp

**Expected behavior**
Version 1.0.3 of pytups is installed.
Version 3.1.1 of pulp is installed.

**Additional context**
Maybe there could be a < for major versions, such as:

pytups<2
pulp<4
ortools<10

Alternatively, and I think it's the correct way, the versions for cornflow_client should be set free and it should be cornflow that has strict versions of depedencies.

Not mandatory, but for cornflow dependencies, this could be achieved by switching to `pyproject.toml` and `uv.lock` instead of `requirements.txt`

I can make a PR if it's needed

Reproduce the problem with `python -m pip install cornflow_client pytups pulp`, then inspect the dependency declarations for cornflow_client and cornflow. Confirm how the current upper bounds affect pytups and pulp, and decide whether the client can loosen them while cornflow retains strict versions. Done means the expected pytups 1.0.3 and pulp 3.1.1 versions can be installed with cornflow_client.

Written by the indexing model from the issue text.