* fix(mcp): over-long reason gets VALIDATION_ERROR and a specific Swedish message
gnubok_reverse_journal_entry / gnubok_undo_sie_import cap `reason` at 500
characters, but exceeding it produced code UNKNOWN_ERROR with message_sv
"Något gick fel. Försök igen." while the cause sat only in message_en.
getStructuredError now infers VALIDATION_ERROR from the message and
getErrorMessage maps it to "Motiveringen får vara högst 500 tecken.".
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* fix(errors): pin the reason-length pattern to 500 and assert the envelope on undo_sie_import
Review findings: the Swedish message hard-codes 500, so the pattern must
match that limit only; the undo_sie_import 501-char test now asserts code
and both localized messages like the reverse test does.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Co-authored-by: Claude Fable 5 <noreply@anthropic.com>