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>

src/data/kb/bossa/progressions.js

@@ -0,0 +1,57 @@
+export default [
+  {
+    id: 'bossa-ipanema',
+    name: 'Ipanema A-section (Imaj7–II7–ii7–♭II7)',
+    rn: ['Imaj7', 'II7', 'ii7', '♭II7', 'Imaj7', '♭II7'],
+    degrees: [0, 2, 2, 1, 0, 1],
+    qualities: ['maj7', 'dom7', 'min7', 'dom7', 'maj7', 'dom7'],
+    bars: [2, 2, 1, 1, 1, 1],
+    mode: 'major',
+    songs: ['The Girl from Ipanema — Jobim', 'Desafinado (same II7 colour)'],
+    tip: 'The II7 is a true dominant-II (Lydian ♭7 colour), and the ♭II7 is the tritone sub of V — the bass slides home by half-step instead of jumping a fifth.',
+  },
+  {
+    id: 'bossa-minor-251',
+    name: 'Minor ii–V–i (Black Orpheus)',
+    rn: ['i7', 'iiø7', 'V7♭9', 'i6'],
+    degrees: [0, 2, 7, 0],
+    qualities: ['min7', 'half_dim', 'dom7', 'min6'],
+    bars: [1, 1, 1, 1],
+    mode: 'minor',
+    songs: ['Manhã de Carnaval (Black Orpheus) — Luiz Bonfá', 'How Insensitive — Jobim (same engine)'],
+    tip: 'The bossa minor tonic is the m6, not the m7 — that major sixth is the saudade. The ♭5 of the iiø7 returns as the ♭9 of the V7.',
+  },
+  {
+    id: 'bossa-blue',
+    name: 'Blue Bossa (16-bar form)',
+    rn: ['i7', 'i7', 'iv7', 'iv7', 'iiø7', 'V7', 'i7', 'i7', '♭iii7', '♭VI7', '♭IImaj7', '♭IImaj7', 'iiø7', 'V7', 'i7', 'i7'],
+    degrees: [0, 0, 5, 5, 2, 7, 0, 0, 3, 8, 1, 1, 2, 7, 0, 0],
+    qualities: ['min7', 'min7', 'min7', 'min7', 'half_dim', 'dom7', 'min7', 'min7', 'min7', 'dom7', 'maj7', 'maj7', 'half_dim', 'dom7', 'min7', 'min7'],
+    bars: [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1],
+    mode: 'minor',
+    songs: ['Blue Bossa — Kenny Dorham'],
+    tip: 'i–iv–iiø–V in minor, then a complete ii–V–I excursion a half-step up (♭II major) in bars 9–12. The jam-session bossa: everyone knows it, nobody minds another chorus.',
+  },
+  {
+    id: 'bossa-one-note',
+    name: 'Chromatic ii–V chain (One Note Samba)',
+    rn: ['iii7', '♭III7', 'ii7', '♭II7'],
+    degrees: [4, 3, 2, 1],
+    qualities: ['min7', 'dom7', 'min7', 'dom7'],
+    bars: [1, 1, 1, 1],
+    mode: 'major',
+    songs: ['One Note Samba — Jobim'],
+    tip: 'iii–VI–ii–V with both dominants tritone-subbed: the bass walks straight down by half-steps while one melody note holds on top. Two grips, alternating, falling.',
+  },
+  {
+    id: 'bossa-corcovado',
+    name: 'Corcovado descent',
+    rn: ['iii6', '♭iii°7', 'ii7', '♭II7', 'Imaj7'],
+    degrees: [4, 3, 2, 1, 0],
+    qualities: ['min6', 'dim7', 'min7', 'dom7', 'maj7'],
+    bars: [1, 1, 1, 1, 2],
+    mode: 'major',
+    songs: ['Corcovado (Quiet Nights) — Jobim', 'How Insensitive — Jobim (same passing-dim device)'],
+    tip: 'A chromatic staircase into the I: m6 → passing diminished → ii → tritone sub. (Charts vary on bar 2 — some write a II7(13) instead of the ♭iii°7; both are in circulation.)',
+  },
+]