Add global timezone/12h-24h setting and improve satellite selection

Global time preferences (Settings > Display > Time & Timezone):
- InterceptTime utility in core/utils.js with timezone + 12h/24h support
- Timezone options: UTC, Local, Eastern, Central, Mountain, Pacific
- Time format: 12-hour (AM/PM) or 24-hour toggle
- Defaults to US/Eastern + 12-hour
- Header nav clock updates to use selected timezone and format
- Weather satellite mode delegates to global InterceptTime
- Settings persist via localStorage, change listeners notify all modes

Weather satellite improvements:
- Satellite dropdown defaults to "All Meteor Satellites" showing all passes
- Can still filter to specific satellite (M2-3, M2-4, M2-4-80K)
- Capture button on pass cards auto-selects the correct satellite

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

static/js/core/app.js

@@ -77,8 +77,23 @@ function declineDisclaimer() {
 
 function updateHeaderClock() {
     const now = new Date();
-    const utc = now.toISOString().substring(11, 19);
-    document.getElementById('headerUtcTime').textContent = utc;
+    const el = document.getElementById('headerUtcTime');
+    const label = document.querySelector('.utc-label');
+    if (typeof InterceptTime !== 'undefined') {
+        if (el) el.textContent = InterceptTime.fullTime(now);
+        if (label) label.textContent = InterceptTime.getLabel() || 'LOCAL';
+    } else {
+        if (el) el.textContent = now.toISOString().substring(11, 19);
+    }
+}
+
+function initTimeSettings() {
+    const tzSelect = document.getElementById('globalTimezoneSelect');
+    const fmtSelect = document.getElementById('globalTimeFormatSelect');
+    if (typeof InterceptTime !== 'undefined') {
+        if (tzSelect) tzSelect.value = InterceptTime.getTimezone();
+        if (fmtSelect) fmtSelect.value = InterceptTime.getHour12() ? '12' : '24';
+    }
 }
 
 // ============== MODE SWITCHING ==============
@@ -447,7 +462,8 @@ function initApp() {
     // Load theme
     loadTheme();
 
-    // Start clock
+    // Start clock and init time settings
+    initTimeSettings();
     updateHeaderClock();
     setInterval(updateHeaderClock, 1000);