Enhance docs

[zmoon]

More xrefs, more text and examples, improve robustness of Tune abcjs display, introduce plot examples (including the polar plot finally)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.32%. Comparing base (facd206) to head (4351792).
⚠️ Report is 69 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #69      +/-   ##
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+ Coverage   92.00%   92.32%   +0.31%     
==========================================
  Files           9        9              
  Lines        1339     1342       +3     
==========================================
+ Hits         1232     1239       +7     
+ Misses        107      103       -4     

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[Copilot]

Pull Request Overview

This PR enriches documentation and examples across the codebase and refines the ABCJS display logic in the Tune class.

• Added examples, cross-references, and detailed parameter/docs in source module docstrings.
• Expanded Jupyter notebooks with new content and introduced a plots.ipynb example.
• Updated Sphinx/ReadTheDocs configuration: added matplotlib, custom CSS, static path, and doctest support.

Reviewed Changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pyproject.toml	Added matplotlib to the doc extras.
pyabc2/sources/*.py	Enhanced docstrings with examples, “See Also” links, notes.
pyabc2/parse.py	Updated _FMT_ABCJS_RENDER_JS to include scale and responsive parameters.
docs/index.md	Added figure directive alt text and an empty nb-exec-table.
docs/examples/*.ipynb	Revamped notebooks with richer examples and added plots.ipynb.
docs/conf.py	Enabled custom static path and CSS.
.readthedocs.yaml	Added sources to extra requirements.
.github/workflows/ci.yml	Enabled --doctest-modules in pytest run configuration.

Comments suppressed due to low confidence (4)

.readthedocs.yaml:14

• The sources extra is referenced in .readthedocs.yaml but there is no corresponding sources entry under [project.optional-dependencies] in pyproject.toml, which may cause installation failures on ReadTheDocs.

        - sources

docs/index.md:26

• [nitpick] The {nb-exec-table} directive is empty and may not render as intended; consider specifying which notebooks to include or removing it if it’s unused.

```{nb-exec-table}

pyabc2/sources/norbeck.py:301

• [nitpick] The See Also section references the generic pyabc2.sources.load_url; it would be clearer to reference norbeck.load_url directly.

    pyabc2.sources.load_url

pyabc2/parse.py:137

• New ABCJS rendering parameters (scale and responsive) were introduced but there are no tests or doctest examples for Tune._repr_html_; consider adding a test to validate correct escaping and output format.

ABCJS.renderAbc("notation-{notation_id:s}", "{abc:s}", {{ scale: 0.87, responsive: "resize" }});