feat: sync cheers-design with impeccable 4.5.0

[myypo]

Port upstream Impeccable 508d7e89 into skills/cheers-design without the
upstream binary:

• replace the brand/product registers with Persuade, Operate, Read and
  Experience visitor modes (product.md becomes operate.md, brand.md folds
  into modes.md)
• add craft-floor, new-work, modes, routing and finish-review references;
  craft becomes a deprecated alias for new-work
• run the direction round by hand instead of concept-seed, store surface
  briefs under .cheers-design/surfaces/, and hand finished builds to a
  fresh reviewer subagent
• rewrite the command references around visitor modes, isolated design
  assessments, an optional impeccable detect scan and bounded
  verification passes, with touch-gesture checks
• follow the eight-section DESIGN.md spec and drop Register from
  PRODUCT.md
• make critique snapshot names unique to the millisecond, include the
  port in URL slugs and warn on invalid metadata

Live mode, variant generation, image comps, hooks, doctor and native
iOS/Android guidance are not ported.