Completes the flagship Roadmap feature. App.jsx lifts a jamFocusChord state (additive,
+10/-0, audio callbacks/refs untouched); JamGuide emits the tapped station's {rootPc,
quality} via onFocusChord; Fretboard halos the 3rd/7th with a degree badge.
Also fixes root-cause guideTones: hasSeventh now keys on real m7/M7 (interval 10/11),
not length>=4 -- so add9/maj6/min6 no longer badge their 5th/6th as a '7'. Fretboard
badge derives its label from the actual interval (belt-and-suspenders). RoadmapTrack
lane self-corrects. Critic returned-then-PASS on re-gate; build + smoke + validator green.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
vadimwit
53d78ce30f