This is the first tag with support for metadata format 2.4.

Fixes #1526.

Co-authored-by: Dmitry Shachnev <[email protected]>

Fixes #1528

See Python bug report at gh-77057 for details. Until we drop support for
Python < 3.13 (where this was fixed upstream), we need to avoid the
unwanted error by checking for it explicitly. Fixes #1534.

The docs previously incorrectly linked to the Semantic Versioning specification.
However, this project has never used that specification. Instead it uses the Python
Version Specification which was originally defined in PEP 440. The
specification explicitly identifies differences between the two
(See https://packaging.python.org/en/latest/specifications/version-specifiers/#semantic-versioning).

- Fix codecs deprecation
- Fix issue with unclosed `<![`
- Fix issue with unclosed HTML tag `<foo`
- Fix issue with unclosed comments
- Add tests which run on the Python 3.14 beta which should automatically update after release

Fixes #1537

New change requires us to monkey patch `locatetagend` to prevent
capturing incomplete tags in code spans.

* Alter footnote ordering so footnotes definitions are listed in the order in which their references appear in the document.
* Add config option, USE_DEFINITION_ORDER, to support previous behavior. 
* Add comprehensive tests for extension.
* Change to the behavior of inlinepatterns by ensuring that inlinepatterns iterate through elements in document order. Previously, in some specific case, elements with nested children had their inline content parsed in reverse order.

Resolves #1367.