Merge origin/main: GNSS integrity, geo file import and cockpit emergencies meet i18n

Conflicts resolved by keeping both sides: the Events group gains
gnss-integrity with a translated label, the cockpit aircraft line shows
main's transponder emergency through a localized formatter (cockpitMath.js
stays i18n-free, like the Context scope line), and the boundary lists keep
both the i18n modules and main's new data modules.

Main's new UI is translated into es and ru: the GNSS Integrity row, legend
and notes; geo file import (button, hints, list actions, every import
error, with numbers passed as placeholders); transponder status names.
Also formats kartaview/viewer.js so format:check passes.

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

src/data/aircraftEmergency.js

@@ -0,0 +1,99 @@
+/**
+ * Transponder emergency status for one aircraft, from the Mode A squawk and
+ * the ADS-B emergency/priority field.
+ *
+ * Emergency squawks are ICAO-standard worldwide: 7500 unlawful interference,
+ * 7600 radio failure, 7700 general emergency. readsb (adsb.lol) also reports
+ * `emergency`, "a superset of the 7x00 squawks": none, general, lifeguard,
+ * minfuel, nordo, unlawful, downed, reserved. OpenSky state vectors carry the
+ * squawk only.
+ *
+ * The status is what the transponder broadcast in THIS poll, never a finding:
+ * crews pass through 7x00 codes while dialling. Highlighting follows the latest
+ * broadcast, which does not confirm an incident or its resolution.
+ */
+
+/** @constant {string} Tint for aircraft broadcasting an emergency (not a priority). */
+export const EMERGENCY_TINT_CSS = '#FF4444';
+
+// Marks catalog text without importing i18n: tools and the server load this module.
+const msg = (text) => text;
+
+const SQUAWK_KINDS = { 7500: 'unlawful', 7600: 'nordo', 7700: 'general' };
+
+const KINDS = {
+  general: { label: msg('General emergency'), severity: 'emergency' },
+  unlawful: { label: msg('Unlawful interference'), severity: 'emergency' },
+  nordo: { label: msg('Radio failure'), severity: 'emergency' },
+  downed: { label: msg('Downed aircraft'), severity: 'emergency' },
+  minfuel: { label: msg('Minimum fuel'), severity: 'priority' },
+  lifeguard: {
+    label: msg('Lifeguard (medical priority)'),
+    severity: 'priority',
+  },
+};
+
+/**
+ * A Mode A code as its four octal digits, else null.
+ * @param {unknown} value
+ * @returns {string|null}
+ */
+export function normalizeSquawk(value) {
+  const code = String(value ?? '').trim();
+  return /^[0-7]{4}$/.test(code) ? code : null;
+}
+
+/**
+ * Emergency status from one observation. Higher severity wins; an ADS-B
+ * emergency wins a tie. A
+ * 7x00 squawk counts even when the ADS-B field says `none`.
+ * @param {{squawk?: unknown, emergency?: unknown}} [observation]
+ * @returns {{kind: string, label: string, severity: 'emergency'|'priority',
+ *   squawk: string|null, source: 'ads-b'|'squawk'}|null} `source` is
+ *   'squawk' when the Mode A code itself names the status (so it can be
+ *   quoted), else 'ads-b'.
+ */
+export function aircraftEmergency({ squawk, emergency } = {}) {
+  const code = normalizeSquawk(squawk);
+  const reported = String(emergency ?? '')
+    .trim()
+    .toLowerCase();
+  const fromAdsb = Object.hasOwn(KINDS, reported);
+  const squawkKind = SQUAWK_KINDS[code] ?? null;
+  const kind =
+    fromAdsb && (KINDS[reported].severity === 'emergency' || !squawkKind)
+      ? reported
+      : squawkKind;
+  if (!kind) return null;
+  return {
+    kind,
+    ...KINDS[kind],
+    squawk: code,
+    source: SQUAWK_KINDS[code] === kind ? 'squawk' : 'ads-b',
+  };
+}
+
+/**
+ * How a summary may phrase the status without flattening it into an incident:
+ * quote the code when the Mode A squawk itself names the status, otherwise
+ * attribute it to the ADS-B emergency field.
+ * @param {{kind?: string, squawk?: string|null, source?: string}|null|undefined} status
+ * @returns {string|null} e.g. 'broadcasting squawk 7700 (general emergency)'
+ *   or 'ADS-B reports general emergency'; null when there is no status.
+ */
+export function emergencyBroadcastPhrase(status) {
+  if (!status || !Object.hasOwn(KINDS, status.kind)) return null;
+  const label = KINDS[status.kind].label.toLowerCase();
+  return status.source === 'squawk' && status.squawk
+    ? `broadcasting squawk ${status.squawk} (${label})`
+    : `ADS-B reports ${label}`;
+}
+
+/**
+ * True when the aircraft is broadcasting an emergency (not a priority status).
+ * @param {{severity?: string}|null|undefined} status
+ * @returns {boolean}
+ */
+export function isEmergency(status) {
+  return status?.severity === 'emergency';
+}