widgets: reload data on update, clock widget, picker previews; README screenshots; 0.2.0

- Glance update() only recomposed the running session, so saved styles (opacity, colours)
  and new forecasts never reached placed widgets; a state version now triggers a reload
- new minimal clock widget (live TextClock, date, current weather), transparent by default
- static preview images for the widget picker, generated previews on Android 15+
- debug builds install next to the release app (app.wetter.debug)

Co-Authored-By: Claude Opus 5.5 <[email protected]>

wetter/app/build.gradle.kts

@@ -17,8 +17,8 @@ android {
         applicationId = "app.wetter"
         minSdk = 29
         targetSdk = 36
-        versionCode = 1
-        versionName = "0.1.0"
+        versionCode = 2
+        versionName = "0.2.0"
     }
 
     // Release key lives outside the repo; without it, release builds fall back to the debug key (local only).
@@ -36,7 +36,13 @@ android {
     }
 
     buildTypes {
+        debug {
+            // installs next to the release app from Obtainium
+            applicationIdSuffix = ".debug"
+            resValue("string", "app_name", "Wetter (Debug)")
+        }
         release {
+            resValue("string", "app_name", "Wetter")
             isMinifyEnabled = true
             isShrinkResources = true
             signingConfig = signingConfigs.findByName("release") ?: signingConfigs.getByName("debug")