kb: add R&B/neo-soul guitar pack

5 progressions (mediant circle, Stevie 6-2-5-1 with 9sus V, maj7
two-chord vamp, D'Angelo Dorian vamp, gospel Amen IV-iv-I) x 2 plays:
m9 slides, m11 colour sets, embellished Mayfield/Hendrix barres,
Dilla-feel barre wash. Comping documents pluck-and-mute, the neo-soul
slide, hammer vocabulary, Cropper 6ths, the Dilla feel. Sourced
Mayfield figures (standard-tuning adaptation flagged). Validator and
build green.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/data/kb/rnb/progressions.js

@@ -0,0 +1,57 @@
+export default [
+  {
+    id: 'rnb-mediant-circle',
+    name: 'Mediant circle (iii7–vi7–ii7–V)',
+    rn: ['iii7', 'vi7', 'ii7', 'V13'],
+    degrees: [4, 9, 2, 7],
+    qualities: ['min7', 'min7', 'min7', 'dom7'],
+    bars: [1, 1, 1, 1],
+    mode: 'major',
+    songs: ['September — Earth, Wind & Fire (rotation family)', 'the soul turnaround started from the iii'],
+    tip: 'The 1-6-2-5 family entered from the mediant — home is implied for three bars before the V finally points at it. Neo-soul lives in that deferral.',
+  },
+  {
+    id: 'rnb-6251',
+    name: 'Soul 6-2-5-1 (with dominant II)',
+    rn: ['vi7', 'II9', 'V9sus', 'I'],
+    degrees: [9, 2, 7, 0],
+    qualities: ['min7', 'dom7', 'sus4', 'maj'],
+    bars: [1, 1, 1, 1],
+    mode: 'major',
+    songs: ["Isn't She Lovely — Stevie Wonder"],
+    tip: 'The II is a secondary dominant (not the polite ii), and the V arrives as a 9sus — suspended, never quite dominant, melting into the I. Stevie\'s whole cadence language in four chords.',
+  },
+  {
+    id: 'rnb-maj7-vamp',
+    name: 'Two-chord maj7 vamp (Imaj7–IVmaj7)',
+    rn: ['Imaj7', 'IVmaj7'],
+    degrees: [0, 5],
+    qualities: ['maj7', 'maj7'],
+    bars: [2, 2],
+    mode: 'major',
+    songs: ['Waiting in Vain — Bob Marley', "Cruisin' — Smokey Robinson (I–ii7 variant)"],
+    tip: 'Two lush chords trading forever — the song is the texture. The same vamp underpins half of modern bedroom R&B; colour it differently every two bars.',
+  },
+  {
+    id: 'rnb-dorian',
+    name: 'Dorian vamp (i7–IV9, D\'Angelo school)',
+    rn: ['i9', 'IV9'],
+    degrees: [0, 5],
+    qualities: ['min7', 'dom7'],
+    bars: [1, 1],
+    mode: 'dorian',
+    songs: ["Spanish Joint — D'Angelo", "Didn't Cha Know — Erykah Badu (i–iv minor variant)", "Brown Sugar — D'Angelo (E Dorian loop)"],
+    tip: 'The IV9 carries the raised 6th that makes it Dorian — the same pair as the funk vamp, slowed to 70 BPM and dragged behind the beat.',
+  },
+  {
+    id: 'rnb-gospel-amen',
+    name: 'Gospel Amen (IV–iv–I)',
+    rn: ['IVmaj7', 'iv6', 'Imaj7'],
+    degrees: [5, 5, 0],
+    qualities: ['maj7', 'min6', 'maj7'],
+    bars: [1, 1, 2],
+    mode: 'major',
+    songs: ['the gospel "Amen" cadence', 'countless soul ballad turnarounds (borrowed iv)'],
+    tip: 'The IV turns minor on its way home — borrowed from the parallel minor, the single most-borrowed chord in soul. One semitone (the 3rd of the IV falling) does all the work.',
+  },
+]