M2 step 4: GNSS mark in the Status Bar; the clock follows the Fix

Q61: a muted G while searching (or the receiver is silent), G with a 2D
Fix, G and the satellite count with a 3D Fix; nothing when GNSS is off.
Verified on the device by a window: 3D Fix, 9 of 11 satellites used
(GPS, GLONASS, BeiDou), HDOP 1.3, Status Bar "G9", and "gnss: clock set".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

src/main.cpp

@@ -91,6 +91,14 @@ static StatusInfo currentStatus() {
     s.sdLevel = storageState.level;
     s.compose = keyMapper.pendingCompose();
     s.unread = irc->totalUnread();
+    if (gnssService && gnssService->on()) {
+        const auto& g = gnssService->state();
+        bool fresh = gnssService->receiving(millis());
+        s.gnss = !fresh || g.fix == gnss::FixType::None ? StatusInfo::Gnss::Searching
+                 : g.fix == gnss::FixType::TwoD        ? StatusInfo::Gnss::TwoD
+                                                       : StatusInfo::Gnss::ThreeD;
+        s.gnssSatellites = g.satellitesUsed;
+    }
     using WifiState = WifiController::State;
     switch (wifi->state()) {
         case WifiState::Connected: {

src/ui/widgets.cpp

@@ -48,6 +48,12 @@ void statusBar(Canvas& c, const StatusInfo& info) {
         case StatusInfo::Wifi::Monitoring: right("MON", kAccent); break;
         case StatusInfo::Wifi::None: break;
     }
+    switch (info.gnss) {  // Q61: muted while searching, normal with a Fix, the count with a 3D Fix
+        case StatusInfo::Gnss::Searching: right("G", kMuted); break;
+        case StatusInfo::Gnss::TwoD: right("G", kText); break;
+        case StatusInfo::Gnss::ThreeD: right("G" + std::to_string(info.gnssSatellites), kText); break;
+        case StatusInfo::Gnss::None: break;
+    }
     if (info.compose) right(std::string("opt ") + (info.compose == '*' ? "" : std::string(1, info.compose)), kAccent);
     c.setTextDatum(top_left);
 }

src/ui/widgets.h

@@ -24,11 +24,13 @@ struct StatusInfo {
     enum class Wifi { None, Searching, Connected, Monitoring } wifi = Wifi::None;
     int wifiBars = 0;  // 0..3 when Connected
     int unread = 0;    // unread messages across Services
+    enum class Gnss { None, Searching, TwoD, ThreeD } gnss = Gnss::None;  // None: GNSS off (Q61)
+    int gnssSatellites = 0;  // used in the Fix
 
     bool operator==(const StatusInfo& o) const {
         return title == o.title && batteryPercent == o.batteryPercent && clock == o.clock &&
                sdPresent == o.sdPresent && sdLevel == o.sdLevel && compose == o.compose && wifi == o.wifi &&
-               wifiBars == o.wifiBars && unread == o.unread;
+               wifiBars == o.wifiBars && unread == o.unread && gnss == o.gnss && gnssSatellites == o.gnssSatellites;
     }
     bool operator!=(const StatusInfo& o) const { return !(*this == o); }
 };