Fix repeater battery % inconsistency and add configurable repeater battery chemistry (#199)

* fix(repeater): unify battery percentage math and add repeater chemistry setting

- Add shared battery percent utility used by connector, repeater status, and telemetry

- Add repeater-specific battery chemistry persistence and service accessors

- Add repeater chemistry selector in Repeater Hub

- Ensure telemetry and status compute percentages consistently from same chemistry

- Add focused battery utility tests

Refs #116

Refs #174

* fix: Flutter Analyzer Errors fixed Recent Merge Compatible

* Unify repeater battery source across status and telemetry

lib/screens/repeater_status_screen.dart

@@ -8,7 +8,9 @@ import '../models/contact.dart';
 import '../models/path_selection.dart';
 import '../connector/meshcore_connector.dart';
 import '../connector/meshcore_protocol.dart';
+import '../services/app_settings_service.dart';
 import '../services/repeater_command_service.dart';
+import '../utils/battery_utils.dart';
 import '../widgets/path_management_dialog.dart';
 
 class RepeaterStatusScreen extends StatefulWidget {
@@ -179,6 +181,12 @@ class _RepeaterStatusScreenState extends State<RepeaterStatusScreen> {
       _dupDirect = directDups;
       _dupFlood = floodDups;
     });
+    final connector = Provider.of<MeshCoreConnector>(context, listen: false);
+    connector.updateRepeaterBatterySnapshot(
+      widget.repeater.publicKeyHex,
+      batteryMv,
+      source: 'status_binary',
+    );
     _recordStatusResult(true);
   }
 
@@ -201,6 +209,18 @@ class _RepeaterStatusScreenState extends State<RepeaterStatusScreen> {
           _uptimeSecs = _asInt(data['uptime_secs']);
           _queueLen = _asInt(data['queue_len']);
           _debugFlags = _asInt(data['errors']);
+          final batteryMv = _batteryMv;
+          if (batteryMv != null) {
+            final connector = Provider.of<MeshCoreConnector>(
+              context,
+              listen: false,
+            );
+            connector.updateRepeaterBatterySnapshot(
+              widget.repeater.publicKeyHex,
+              batteryMv,
+              source: 'status_text',
+            );
+          }
         } else if (data.containsKey('noise_floor')) {
           _noiseFloor = _asInt(data['noise_floor']);
           _lastRssi = _asInt(data['last_rssi']);
@@ -590,18 +610,24 @@ class _RepeaterStatusScreenState extends State<RepeaterStatusScreen> {
   }
 
   String _batteryText() {
-    if (_batteryMv == null) return '—';
-    final percent = _batteryPercentFromMv(_batteryMv!);
-    final volts = (_batteryMv! / 1000.0).toStringAsFixed(2);
+    final connector = context.watch<MeshCoreConnector>();
+    final batteryMv =
+        connector.getRepeaterBatteryMillivolts(widget.repeater.publicKeyHex) ??
+        _batteryMv;
+    if (batteryMv == null) return '—';
+    final percent = estimateBatteryPercentFromMillivolts(
+      batteryMv,
+      _batteryChemistry(),
+    );
+    final volts = (batteryMv / 1000.0).toStringAsFixed(2);
     return '$percent% / ${volts}V';
   }
 
-  int _batteryPercentFromMv(int millivolts) {
-    const minMv = 3000;
-    const maxMv = 4200;
-    if (millivolts <= minMv) return 0;
-    if (millivolts >= maxMv) return 100;
-    return (((millivolts - minMv) * 100) / (maxMv - minMv)).round();
+  String _batteryChemistry() {
+    final settingsService = context.read<AppSettingsService>();
+    return settingsService.batteryChemistryForRepeater(
+      widget.repeater.publicKeyHex,
+    );
   }
 
   String _clockText() {