Blank content means content_html is the body (no 422 for
content_html-only translations, a regression from the markdown alt fix);
any other content is handled as markdown, so a body opening with a tag
gets its inline image label and keeps its code samples.
quick-261104-xae, review WR-02.
POST /_journal/api/v1/images/alt writes the alt of a markdown post into
its source: the inline image  outside code
(classes.SetMarkdownImageAlt) or a raw img outside code
(classes.SetImageAltOutsideCode), so the next content save keeps it. An
image the markdown does not hold that way is refused with 422
changes.N.src and nothing is written.
- 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
- classes.FixStoredHeadings converts stored H1 in post content (every
locale) and category pillar text, in one transaction with a RecordSaved
and a site cache purge per changed record
- journal:fix-headings, a dry run unless --apply, refuses with exit code 1
while the H1 setting is off
- GET/PUT /_journal/api/v1/settings and POST /fix-headings {dry_run} for
golem15.journal.manage_settings; 409 with the refusal while the setting
is off
