Headings without an explicit label can now be assigned automatic
identifiers based on the heading text, making them linkable in a
generated table of contents. The extension is available for the
typst reader but is off by default; enable it with
`-f typst+auto_identifiers`. The related `gfm_auto_identifiers` and
`ascii_identifiers` extensions are also made available.
Closes#11041.
Text.Pandoc.Readers.Typst.Parsing: PState gains sOptions,
sIdentifiers, and sLogMessages fields, and now has
HasReaderOptions, HasIdentifierList, and HasLogMessages
instances, allowing reuse of the shared registerHeader. (Not an
API change.)
Co-Authored-By: Claude <noreply@anthropic.com>
