parseRobots accepted 2027-02-30 (Date.parse rolls it over) and refused
max-snippet:+5, both unlike classes/robots_value.go. A value it could not
parse showed every group as Inherit and the first click serialised the
empty model, dropping the stored directives. Dates are now checked as
calendar dates, a sign is accepted, and an unparsed value is kept with a
note, the controls off and an explicit Reset.
vitest + happy-dom tests of the UI-SPEC backstops: E1 status thresholds
(29/30 characters, 580/581 px; 119/120 and 920/921 for descriptions)
with a mocked measureText and the counter's wrap contract; the E2 grammar
over every directive combination, the emitted values and the stacking
contract with unclipped en and pl labels; the E3 effective title,
word-boundary truncation and keyphrase stem matching; each E4 lint rule
and a clean file; E6 apply gating. happy-dom has no layout engine, so the
narrow-width rows check the stylesheet's layout contract.
