feat: Konfigurierbare Sync-Intervalle + Über-Sektion (v1.1.0) (#1)

* feat: WiFi-Connect Auto-Sync + Debug Logging [skip ci]

- WiFi-Connect Auto-Sync via NetworkCallback + Broadcast (statt WorkManager)
- onResume Auto-Sync mit Toast-Feedback (nur Success)
- File-Logging Feature für Debugging (letzte 500 Einträge)
- Settings: Debug/Logs Section mit Test-Button
- FileProvider für Log-Sharing
- Extensive Debug-Logs für NetworkMonitor + MainActivity
- Material Design 3 Migration (alle 17 Tasks)
- Bug-Fixes: Input underlines, section rename, swipe-to-delete, flat cards

PROBLEM: WiFi-Connect sendet Broadcast aber MainActivity empfängt nicht
→ Benötigt logcat debugging auf anderem Gerät

* 🐛 fix: Remove WiFi-Connect related code and UI elements to streamline sync process

* feat: Konfigurierbare Sync-Intervalle + Über-Sektion (v1.1.0)

## Neue Features

### Konfigurierbare Sync-Intervalle
- Wählbare Intervalle: 15/30/60 Minuten in Settings
- Transparente Akkuverbrauchs-Anzeige (0.2-0.8% pro Tag)
- Sofortige Anwendung ohne App-Neustart
- NetworkMonitor liest Intervall dynamisch aus SharedPreferences

### Über-Sektion
- App-Version & Build-Datum Anzeige
- Klickbare Links zu GitHub Repository & Entwickler-Profil
- Lizenz-Information (MIT License)
- Ersetzt alte Debug/Logs Sektion

## Verbesserungen

- Benutzerfreundliche Doze-Mode Erklärung in Settings
- Keine störenden Sync-Fehler Toasts mehr im Hintergrund
- Modernisierte README mit Badges und kompakter Struktur
- F-Droid Metadaten aktualisiert (changelogs + descriptions)

## Technische Änderungen

- Version Bump: 1.0 → 1.1.0 (versionCode: 1 → 2)
- BUILD_DATE buildConfigField hinzugefügt
- PREF_SYNC_INTERVAL_MINUTES Konstante in Constants.kt
- NetworkMonitor.startPeriodicSync() nutzt konfigurierbare Intervalle
- SettingsActivity: setupSyncIntervalPicker() + setupAboutSection()
- activity_settings.xml: RadioGroup für Intervalle + About Cards

android/app/src/main/res/layout/activity_editor.xml

@@ -5,31 +5,46 @@
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
+    android:background="?attr/colorSurface"
     android:fitsSystemWindows="true">
 
+    <!-- Material 3 Toolbar -->
     <com.google.android.material.appbar.MaterialToolbar
         android:id="@+id/toolbar"
         android:layout_width="match_parent"
         android:layout_height="?attr/actionBarSize"
+        android:elevation="0dp"
         app:navigationIcon="@android:drawable/ic_menu_close_clear_cancel"
-        app:title="@string/edit_note" />
+        app:title="@string/edit_note"
+        app:titleTextAppearance="@style/TextAppearance.Material3.TitleLarge" />
 
+    <!-- Material 3 Outlined TextInputLayout with 16dp corners -->
     <com.google.android.material.textfield.TextInputLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_margin="16dp"
         android:hint="@string/title"
-        style="@style/Widget.Material3.TextInputLayout.OutlinedBox">
+        style="@style/Widget.Material3.TextInputLayout.OutlinedBox"
+        app:boxCornerRadiusTopStart="16dp"
+        app:boxCornerRadiusTopEnd="16dp"
+        app:boxCornerRadiusBottomStart="16dp"
+        app:boxCornerRadiusBottomEnd="16dp"
+        app:endIconMode="clear_text"
+        app:counterEnabled="true"
+        app:counterMaxLength="100">
 
         <com.google.android.material.textfield.TextInputEditText
             android:id="@+id/editTextTitle"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:inputType="text"
-            android:maxLines="2" />
+            android:maxLines="2"
+            android:maxLength="100"
+            android:textAppearance="@style/TextAppearance.Material3.BodyLarge" />
 
     </com.google.android.material.textfield.TextInputLayout>
 
+    <!-- Material 3 Outlined TextInputLayout for Content -->
     <com.google.android.material.textfield.TextInputLayout
         android:layout_width="match_parent"
         android:layout_height="0dp"
@@ -38,7 +53,14 @@
         android:layout_marginEnd="16dp"
         android:layout_marginBottom="16dp"
         android:hint="@string/content"
-        style="@style/Widget.Material3.TextInputLayout.OutlinedBox">
+        style="@style/Widget.Material3.TextInputLayout.OutlinedBox"
+        app:boxCornerRadiusTopStart="16dp"
+        app:boxCornerRadiusTopEnd="16dp"
+        app:boxCornerRadiusBottomStart="16dp"
+        app:boxCornerRadiusBottomEnd="16dp"
+        app:endIconMode="clear_text"
+        app:counterEnabled="true"
+        app:counterMaxLength="10000">
 
         <com.google.android.material.textfield.TextInputEditText
             android:id="@+id/editTextContent"
@@ -46,7 +68,9 @@
             android:layout_height="match_parent"
             android:gravity="top|start"
             android:inputType="textMultiLine"
-            android:scrollbars="vertical" />
+            android:scrollbars="vertical"
+            android:maxLength="10000"
+            android:textAppearance="@style/TextAppearance.Material3.BodyMedium" />
 
     </com.google.android.material.textfield.TextInputLayout>