App 2.19.7: meter AC charging too, while the app runs

A session runs whenever power flows into the pack, AC or DC; gaps the
head unit slept through are dropped as before. Dashboard and server
texts no longer say DC only.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LhzAVaUyqcw5PkGjz4mWW6

app/build.gradle

@@ -34,8 +34,8 @@ android {
         applicationId "com.stinnesbeck.nilsmg4"
         minSdk 27
         targetSdk 36
-        versionCode 105
-        versionName "2.19.6"
+        versionCode 106
+        versionName "2.19.7"
 
         // Nothing about the server ships in the APK: its URL and ingest token are entered in
         // the app's Server tab (ServerConfig), and the database is only reachable by the server.