Add initial ASV benchmarks

[ojeda-e]

Fixes #84

Description

Changes made in this Pull Request:

• Added ASV json config with uv envs.
• Included outputs of benchmarks in .gitignore.
• Added basic benchmark.
• Created README with steps and brief explanations to run ASV.

PR Checklist

• Issue raised/referenced?
• [N/A] Tests updated/added?
• Documentation updated/added?
• CHANGELOG file updated?

Notes:

• Right now everything lives in a single file (benchmarks/membranecurvature.py), to cover MembraneCurvature.run() performance across system sizes, surface methods (Fourier and binning), Fourier modes, and multi-frame trajectories.
• I’m treating this as a first pass rather than the final benchmark layout. Longer term, I’d like to split benchmarks into one file per module under membrane_curvature/ For example base, binning_surface, fourier_surface, etc. Then we could track performance at both the analysis API level and for lower-level building blocks. This is particularly interesting because there is a difference in performance between binning and fourier, but also one when increasing the fourier modes.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (f80c72d) to head (f197846).

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[ojeda-e]

@orbeckst I started with the approach you suggested (minimal/simple becnhmarks) with its config and README. For anytime you are available I'll be happy to receive your feedback. Thanks!