Add pre-commit config with linting for C++ and Python

[ianthomas23]

This adds linting of C++ and Python via pre-commit, fixing #1.

Configuration is taken from a combination of sparrow and mamba.

• clang-format for C++ is from sparrow with the sparrow-specific import order removed, I've taken this as an example of recent good practice and I am not particularly concerned by exactly which rules we do and do follow, along as there are some rules that are enforced. We can bikeshed if anyone wants to 😃.
• Remainder of .pre-commit-config.yaml is a subset of those from mamba to enforce some generic checks plus Python linting via pyupgrade and ruff.
• There are a few ruff settings in a new pyproject.toml. It is a little strange to have a pyproject.toml in a non-Python project, but this is a common place for such tools to look for configuration settings.

I've added pre-commit as a new dev dependency in the two micromamba environment files - maintainers should update their environments accordingly. When this is done pre-commit will be automatically run on commits, and can be manually run using

pre-commit run --all-files

pre-commit.ci should automatically run in CI on PRs to identify and fix problems, we will have to see if it works. If/when it does, there will be a lot of changes to pretty much all of the C++ and Python files as part of this PR.

There is no linting of JavaScript/TypeScript yet as there are only a couple of TypeScript files in the wasm testing only.

[ianthomas23]

pre-commit.ci did kick in and correct about 1000 lines of code!

[codecov]

Codecov Report

❌ Patch coverage is 88.07339% with 65 lines in your changes missing coverage. Please review.
✅ Project coverage is 88.23%. Comparing base (ade2c75) to head (b5fa4dd).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/utils/common.cpp	30.00%	14 Missing ⚠️
src/subcommand/status_subcommand.cpp	76.47%	12 Missing ⚠️
src/subcommand/merge_subcommand.cpp	84.37%	10 Missing ⚠️
src/subcommand/diff_subcommand.cpp	90.78%	7 Missing ⚠️
src/subcommand/tag_subcommand.cpp	82.85%	6 Missing ⚠️
src/wrapper/repository_wrapper.cpp	64.70%	6 Missing ⚠️
src/utils/progress.cpp	84.61%	2 Missing ⚠️
src/subcommand/checkout_subcommand.cpp	88.88%	1 Missing ⚠️
src/subcommand/init_subcommand.cpp	90.90%	1 Missing ⚠️
src/subcommand/log_subcommand.cpp	97.56%	1 Missing ⚠️
... and 5 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #121      +/-   ##
==========================================
+ Coverage   87.98%   88.23%   +0.25%     
==========================================
  Files          60       60              
  Lines        2489     2619     +130     
  Branches      308      309       +1     
==========================================
+ Hits         2190     2311     +121     
- Misses        299      308       +9     

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