ConvertContentH1 rewrites content only when it is HTML; a markdown
source, its code samples included, is kept byte for byte and only its
rendered content_html is converted, on API saves, imports,
journal:fix-headings and translations. ConvertH1 and SetImageAlt keep
the bytes of an unfinished tag at the end of the input.
- POST /_journal/api/v1/images/alt {dry_run, changes} sets alt on the
matching img of default or translated content through the tokenizer,
all or nothing (422), with a RecordSaved per changed post
- MCP journal_get_settings, journal_update_settings, journal_fix_headings
(manage_settings) and journal_set_image_alt (access_posts, destructive)
- journal:fix-headings help names its output and the refusal
