Replace pdm dependency solver with uv

[spwoodcock]

What type of PR is this? (check all applicable)

• 🍕 Feature
• 🐛 Bug Fix
• 📝 Documentation
• 🧑‍💻 Refactor
• ✅ Test
• 🤖 Build or CI
• ❓ Other (please specify)

Describe this PR

uv:

• uv was released not too long ago and has since almost gained feature parity with other tools like pdm.
• It's written in rust and is orders of magnitude faster at locking dependencies: a minor win, but a nice one nonetheless.
• It also allows you to run different versions of Python on your system very easily.
• Thanks @Pradip-p for pointing this tool out!

What I did:

• Replaced all usage of pdm with uv.
• Overhauled the backend dockerfile to work with uv and be a bit cleaner.
• Updated docs around using pdm.

Minor caveats:

• We can no longer use the dynamic field in pyproject.toml: dynamic=["version"].
• This isn't a big deal - we can just hardcode it. The version updating is done by commitizen anyway, so nothing lost.

Bonus:

• There is also a pre-commit hook for uv, allowing us to re-lock automatically if someone updates the a backend dependency and forgets to lock 🎉 (which would break the docker build otherwise).

Key things of note:

• uv lock re-locks dependencies, including all optional groups.
• uv sync installs dependencies locally.
• uv run ... runs a command using installed dependencies venv.
• It's also possible to manage multiple python versions on the system with uv python list and uv python install.
• pdm publish --> uv publish for publishing to pypi.

Note: I plan to talk about using this tool with the dev teams when I visit NAXA 👍

Screenshots

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Checklist before requesting a review

• 📖 Read the FMTM Contributing Guide: https://github.com/hotosm/fmtm/blob/main/CONTRIBUTING.md
• 📖 Read the HOT Code of Conduct: https://docs.hotosm.org/code-of-conduct
• 👷‍♀️ Create small PRs. In most cases, this will be possible.
• ✅ Provide tests for your changes.
• 📝 Use descriptive commit messages.
• 📗 Update any related documentation and include any relevant screenshots.

[optional] What gif best describes this PR or how it makes you feel?

[Pradip-p]

When I heard about UV, it always triggered one question: what exactly makes it faster than other tools like pip, PDM, or Poetry?

it seems UV uses heavy parallelization, advanced caching, and an optimized way to access metadata from PYPI. Instead of downloading entire package wheels, it queries the zip file’s Central Directory and fetches only the needed metadata using file offsets, avoiding unnecessary downloads and speeding up dependency resolution.

Am I understanding this correctly? Let me know your thoughts! @spwoodcock @nrjadkry @Sujanadh

[spwoodcock]

You are definitely right when I comes the install part!

When it comes to speeding up the locking, the key factor here is that this is a library written in rust, a much lower level programming language with better parallelization than python (as you mention).

They most likely use pyo3 to generate Python bindings for the underlying rust library, meaning we get to install and use it from Python 😄

Same concept for ruff, one of astral's other tools