Addresses Copilot's round-13 review on #2035. Two suppressed comments, both
real, both in the required-group work from round 7 rather than in the recent
preview rework.
1. `{a,a}` is ONE requirement named twice, but `requiredGroups` stored it as
a two-name group, so everything downstream read it as "either of these
will do". The TUI was left with a form it could not submit: its
`length === 1` test marked `a` optional while ResourceTestModal's guard
still refused a blank. The web panel offered the useless hint
"Any one of: a, a". Names are now deduplicated within the expression --
expansion still emits both occurrences (`x://{a,a}` -> `x://1,1`), which
RFC 6570 requires.
2. The per-field hint used `find`, so a variable in several shared groups
advertised only the first. With `{a,b}{b,c}{a,c}`, filling `b` satisfies
the first two and every visible hint then looks met while Read Resource
stays disabled on the unmet `{a,c}` -- a requirement with nothing on
screen pointing at it.
Fields now hint every shared group they sit in. That alone is not enough,
because no per-field hint can say WHICH group is still outstanding, so
the form states it directly: "Still needed: a or c", built from the same
`unmetRequiredGroups` the submit gate uses, so the message and the button
cannot disagree. `hasRequiredValues` is no longer called here -- the
panel derives both from the one list.
npm run ci passes.
Signed-off-by: cliffhall <cliff@futurescale.com>