refine(wallet): the balance readout scans as one column, not a barcode

Seeing it on the node settled the shape. Two rows of per-cell delays
read as a dense flicker — closer to a progress bar than a display, and
short enough against the row's text to look like an underline.

Three rows laid out column-first fixes both: the three cells of a column
now share a delay, so the lit column travels across as a single scan
line, and at 11px the matrix sits with the text rather than under it.

Verified in a real browser against the live node with the balance RPCs
held open: five placeholders, five distinct rail colours (white, orange,
yellow, purple, blue), 42 cells each, all animating, each announcing
what it is waiting for — and no "0 sats" anywhere on screen while the
calls were in flight. They gave way to real figures on arrival, with
Lightning's genuine 0 correctly shown as a figure rather than left
shimmering.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

neode-ui/src/components/__tests__/BalanceAmount.test.ts

@@ -59,9 +59,17 @@ describe('BalanceAmount', () => {
     expect(w.html()).not.toMatch(/background:\s*#|rgb\(/)
   })
 
-  it('renders enough cells to read as a matrix', () => {
+  it('renders a 14x3 matrix scanned column by column', () => {
+    // Column-first layout is what makes the lit column travel across as one
+    // scan line; per-cell delays would make it crawl diagonally instead.
     const w = mount(BalanceAmount, { props: { sats: null } })
-    expect(w.findAll('.balance-pixel').length).toBe(28)
+    const cells = w.findAll('.balance-pixel')
+    expect(cells.length).toBe(42)
+    // The three cells of a column share a delay; the next column steps on.
+    const delay = (i: number) => cells[i]?.attributes('style') ?? ''
+    expect(delay(0)).toBe(delay(1))
+    expect(delay(1)).toBe(delay(2))
+    expect(delay(3)).not.toBe(delay(2))
   })
 })