An en-us corpus item is accepted by check_panel (open does not revalidate), so
only is_language_tag in create refuses the panel en-us.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
indented() is asserted for CR, VT, FF, NEL, LS, PS and CRLF without str::lines.
The mint instructions said 1 to 8 entries but only 64 per language is enforced;
the prose now says what is enforced. PROMPT_SOURCE_DIGEST is computed from the
source, so it moves with this edit and needs no literal update.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Reject a singleton with nothing after it (x, en-x, en-u), singleton
directly after singleton, one-digit and two-digit non-region subtags
(en-0, en-12), and uppercase private-use subtags (x-AB).
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>