Fix histogram bin midpoints + other doc improvements

[tpvasconcelos]

This pull request introduces several improvements and updates across the codebase, focusing on documentation clarity, developer experience, and a minor bug fix in histogram binning. The most significant changes include updating the basic examples throughout the documentation, improving how Plotly.js is loaded for the docs (with a CDN fallback), fixing histogram bin center calculation, and cleaning up test and manifest files. Additionally, developer tooling is enhanced with a Cursor worktree config.

Documentation and Example Updates:

• Updated all basic examples in the documentation and code to use new sample generation logic and consistent parameters for clarity and reproducibility (README.md, docs/index.md, docs/getting_started/getting_started.md, cicd_utils/ridgeplot_examples/_basic.py, cicd_utils/ridgeplot_examples/_basic_hist.py, src/ridgeplot/__init__.py) [1] [2] [3] [4] [5] [6].

• Improved documentation build process to bundle a local copy of plotly.min.js as a fallback if the CDN is unavailable, and updated the Sphinx template to load Plotly dynamically (docs/_templates/base.html, docs/Makefile, Makefile, docs/conf.py, MANIFEST.in) [1] [2] [3] [4] [5].

Bug Fixes:

• Fixed the computation of histogram bin centers in bin_trace_samples to use actual bin centers instead of edges, ensuring correct histogram rendering (src/ridgeplot/_hist.py).

Developer Experience and CI/CD:

• Added a basic .cursor/worktrees.json config to support Cursor worktrees for improved developer workflow.
• Cleaned up test artifacts and manifest entries: removed JPEGs from regression test artifacts and adjusted manifest to exclude unnecessary files and include relevant configs (MANIFEST.in).
• Updated changelog to reflect these changes (docs/reference/changelog.md).

Code Quality and Maintenance:

• Enforced explicit figure width and height in all example plots and improved error handling in example generation (cicd_utils/ridgeplot_examples/_base.py) [1] [2] [3].
• Updated image references in documentation from .jpg to .jpeg for consistency (docs/getting_started/getting_started.md, MANIFEST.in) [1] [2].

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (6445208) to head (414ce85).
⚠️ Report is 8 commits behind head on ruff-py310.

Additional details and impacted files

@@             Coverage Diff              @@
##           ruff-py310      #364   +/-   ##
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  Coverage      100.00%   100.00%           
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  Files              18        18           
  Lines             657       657           
  Branches           85        85           
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  Hits              657       657           

Flag	Coverage Δ
combined-src	100.00% <100.00%> (ø)

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[tpvasconcelos]

@codex review