fix(cockpit): show wind from 359.6° as 0°, not 360°

formatCockpitWindDirection rounded the bearing and printed that number, so wind from 359.5° or more read "N · 360°". Take the rounded degrees modulo 360 so north reads 0°.

src/ui/cockpitPresentation.test.mjs

@@ -0,0 +1,10 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { formatCockpitWindDirection } from './cockpitPresentation.js';
+
+test('wind just west of north reads 0°, not 360°', () => {
+  assert.equal(formatCockpitWindDirection(90), 'E · 90°');
+  assert.equal(formatCockpitWindDirection(0), 'N · 0°');
+  assert.equal(formatCockpitWindDirection(359.4), 'N · 359°');
+  assert.equal(formatCockpitWindDirection(359.6), 'N · 0°');
+});