i18n(ja): apply review round 2

Catalog fixes from the second review round (squawk 7600/7700 names,
transit occupancy, radio category, cyclone advisory wording, Orbital Watch,
validation and hint texts), cockpit distances keep "km" in Japanese as in
Chinese, the CCTV context line uses the translated view band, and the
Japanese layer status line no longer splits "1分以内".

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/ui/cockpitContext.js

@@ -1,6 +1,6 @@
 /** Contact readouts and nearby-signal presentation for the Cockpit controller. */
 import * as Cesium from 'cesium';
-import { formatNumber, getLocale, t, tn } from '../i18n/index.js';
+import { formatNumber, t, tn } from '../i18n/index.js';
 import { unitLabel } from './unitLabels.js';
 import {
   bearingBetweenCoordinates,
@@ -8,14 +8,17 @@ import {
   relativeBearing,
   resolveCockpitContextReadout,
 } from '../cockpitMath.js';
-import { formatCockpitDistance } from './cockpitPresentation.js';
+import {
+  cockpitUnitCase,
+  formatCockpitDistance,
+} from './cockpitPresentation.js';
 
 /** The Context scope line in the active language (see cockpitMath.js). */
 const LOCALIZED_CONTEXT_SCOPE = Object.freeze({
   window: ({ label, radiusKm }) =>
     t('{label} · {radius} AIR/SEA WINDOW', {
       label,
-      radius: `${radiusKm === null ? '—' : formatNumber(radiusKm)}\u00a0${getLocale().startsWith('zh-') ? unitLabel('km') : unitLabel('km').toUpperCase()}`,
+      radius: `${radiusKm === null ? '—' : formatNumber(radiusKm)}\u00a0${cockpitUnitCase(unitLabel('km'))}`,
     }),
   installations: ({ scope, coverage }) =>
     t('{scope} · INSTALLATIONS {coverage}', { scope, coverage }),