Compass: a fix while standing still (no heading) is subdued, not the no-receiver alarm

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz

lib/widgets/gps_compass.dart

@@ -16,6 +16,9 @@ class GpsCompass extends StatelessWidget {
   bool get _hasSignal => heading != null;
   bool get _isAcquiring => gpsState == 'acquiring';
 
+  /// A fix but no heading: standing still, where GNSS cannot tell direction. Not a fault.
+  bool get _isStill => gpsState == 'fix' && !_hasSignal;
+
   String get _displayHeading {
     if (!_hasSignal) return 'N/A';
     return '${(heading! % 360).round()}';
@@ -50,8 +53,13 @@ class GpsCompass extends StatelessWidget {
     final theme = AppTheme.of(context);
 
     // No signal = subdued color, valid = foreground
-    // Heading: foreground; acquiring: caution; no receiver at all: alarm.
-    final iconColour = _hasSignal ? theme.foreground : (_isAcquiring ? theme.caution : theme.alarm);
+    // Heading: foreground; standing still with a fix: subdued; acquiring: caution;
+    // no receiver at all: alarm.
+    final iconColour = _hasSignal
+        ? theme.foreground
+        : (_isStill
+              ? theme.subdued
+              : (_isAcquiring ? theme.caution : theme.alarm));
 
     // Convert to radians, 0 = no rotation when no signal
     final angle = _hasSignal ? (heading! * math.pi / 180.0) : 0.0;
@@ -80,7 +88,7 @@ class GpsCompass extends StatelessWidget {
             child: Text(
               _hasSignal
                   ? "$_displayHeading $_compassDirection"
-                  : (_isAcquiring ? "ACQ" : "N/A"),
+                  : (_isStill ? "—" : (_isAcquiring ? "ACQ" : "N/A")),
               style: TextStyle(
                 fontSize: 80,
                 color: theme.subdued, // less emphasis on text, let the icon have semantic colour