v7.3: reliable device_id with SSH fallback

- Add JSch SSH library dependency
- Persistent device_id cache in DataStore (not just memory)
- Load cached device_id on app start
- Only fetch if missing or 'unknown'
- 30-second timeout for /api/1/info endpoint
- SSH fallback to root@192.168.0.10:22 when API fails
- Retry device_id fetch after successful landmark poll
- Fallback order: DataStore cache → API → SSH
- Build signed APK at varroa-v7.3.apk

app/build.gradle.kts

@@ -13,8 +13,8 @@ android {
         applicationId = "com.adamaps.varroa"
         minSdk = 26
         targetSdk = 34
-        versionCode = 8
-        versionName = "1.7.1"
+        versionCode = 9
+        versionName = "1.7.3"
 
         vectorDrawables {
             useSupportLibrary = true
@@ -76,5 +76,7 @@ dependencies {
     ksp(libs.room.compiler)
     // WorkManager (background uploads)
     implementation(libs.work.runtime.ktx)
+    // SSH connectivity for device_id fallback
+    implementation("com.jcraft:jsch:0.1.55")
     debugImplementation(libs.androidx.ui.tooling)
 }