chore(deps-dev): bump m2r2 from 0.3.4 to 2.1.0

[dependabot]

Bumps m2r2 from 0.3.4 to 2.1.0.

Changelog

Sourced from m2r2's changelog.

Version 2.1.0 (2026-09-24)

• Support Mistune 3.3.

Version 2.0.0 (2026-09-24)

Breaking changes

• Replace the Python disable_inline_math argument with inline_math, accepting "legacy", "dollar", or None.
• Require Mistune 3.2 so footnote rendering shares document definitions.
• Remove the renderer argument from M2R2. SphinxM2R2 constructs a converter from a docutils document for Sphinx integrations.
• Make RestRenderer render only the document body when it is used directly with Mistune. M2R2 writes the role and substitution definitions for a complete document.
• Shorten generated substitution names to a type prefix and twelve hexadecimal hash characters.
• Discard Markdown link titles, which RST references cannot represent.
• Resolve fragment links under Sphinx with the m2r-anchor role instead of :ref:.
• Render links in headings with plain text and anonymous references so section ids stay readable.
• Start absolute mdinclude paths at the Sphinx source directory instead of the filesystem root.

Fixes and additions

• Resolve relative Markdown image paths from the included file's directory, including nested includes. Keep image substitutions distinct when different files use the same relative image path.
• Convert GitHub alerts ([!NOTE], [!TIP], [!IMPORTANT], [!WARNING], and [!CAUTION]) into RST admonitions.
• Add dollar-delimited inline math with inline_math="dollar", supporting $...$ and dollar-backtick delimiters. Keep "legacy" as the default and use None to disable inline math.
• Add --inline-math legacy and --inline-math dollar to the CLI. Keep --disable-inline-math to turn off inline math.
• Add the Sphinx setting m2r_inline_math. Keep m2r_disable_inline_math as a deprecated alias with a warning. An explicit new setting takes precedence.
• Write document definitions after footnotes render, so links and images in footnotes have their definitions.
• Preserve emphasis around links and inline markup within link text by using substitutions where RST cannot express the nesting directly.
• Render empty links as empty references and move footnote references out of link text.
• Prevent references from nesting inside links. Linked images lose their own targets, and plain link text escapes characters that create RST references.
• Render strikethrough content as HTML and keep its inline Markdown formatting.
• Preserve backslashes in text.
• Derive image alt text from plain text.
• Resolve same-page and cross-page links to Markdown headings by their GitHub anchors. Resolve explicit RST labels before generated heading anchors with the same name.
• Add start-after, end-before, lines, literal, code, number-lines, name, and class to mdinclude. Reject its parser option.
• Track files read by mdinclude so Sphinx rebuilds them when they change.

Version 1.1.0 (2026-09-18)

• Add the m2r2.mdinclude Sphinx extension. It provides the mdinclude directive and leaves .md files to another parser.

Version 1.0.1 (2026-09-18)

• Keep underscores literal under no_underscore_emphasis with Mistune 3.3's emphasis parser.
• Keep _ and * inside bare URLs and email addresses from being read as emphasis with Mistune 3.3.
• Render autolinks through a new standalone_hyperlink renderer method.

Version 1.0.0 (2026-02-11)

• Drop support for Python < 3.9.
• Upgrade to Mistune 3.0+.
• Rename the converter class to M2R2, retaining M2R as an alias.
• Deprecate Sphinx config no_underscore_emphasis in favor of m2r_no_underscore_emphasis.
• Support inline images, including images in table cells, using RST substitutions.

... (truncated)

Commits

• 2f487f3 fixes
• 3eb4b0c support mistune3.3
• 6333e09 Merge pull request #76 from CrossNox/v2.0
• 0b5f887 fix on reradme
• abd1624 update date
• 2215fa1 Name CLI paths and conversion results clearly
• 41ee246 Name visible heading text state clearly
• 9d89957 Name GitHub alert parser state clearly
• 0a6e985 Name selected lines and range bounds clearly
• 53699d1 Name renderer values by their roles
• Additional commits viewable in compare view

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