randomFullTablePrompt now rejects any (verb, tense) combo where any
form has regularity != "regular" and keeps retrying (40 attempts) until
a fully-regular combo is picked. Full Table practice is meant for
drilling regular conjugation patterns — irregular tables belong in the
Irregularity Drills mode.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>