kb: add bossa nova guitar pack
5 progressions (Ipanema A-section, minor ii-V-i with m6 tonic, Blue
Bossa 16-bar, One Note Samba chromatic chain, Corcovado descent) x 2
plays on alternating root-string sets. Joao Gilberto rhythm layers
documented (thumb surdo + syncopated block, two-bar tied pattern,
partido alto contrast), improv map, sourced Ipanema melodic cell.
Validator caught 6 quality mismatches (6/9 grips on maj7/min7 steps)
- content fixed, gate untouched. Validator and build green.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
vadimwit
de0071f7bf