Apply imePadding and set windowSoftInputMode

This commit ensures the UI correctly adjusts for the on-screen keyboard by:
- Adding `imePadding()` to the `Scaffold` modifier in `DiffCheckerScreen.kt`.
- Setting `android:windowSoftInputMode="adjustResize"` for `MainActivity` in `AndroidManifest.xml`.

Author: JahidHasanCO

app/src/main/AndroidManifest.xml

@@ -15,7 +15,8 @@
         <activity
             android:name=".presentation.MainActivity"
             android:exported="true"
-            android:theme="@style/Theme.DiffChecker">
+            android:theme="@style/Theme.DiffChecker"
+            android:windowSoftInputMode="adjustResize">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 

app/src/main/java/dev/jahidhasanco/diffly/presentation/screen/DiffCheckerScreen.kt

@@ -10,6 +10,7 @@ import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.imePadding
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.wrapContentWidth
@@ -65,7 +66,7 @@ fun DiffCheckerScreen(viewModel: MainViewModel) {
     var expanded by remember { mutableStateOf(false) }
     var selectedViewType by remember { mutableStateOf(DiffViewType.TWO_SIDE) }
     Scaffold(
-        modifier = Modifier.fillMaxSize(),
+        modifier = Modifier.fillMaxSize().imePadding(),
         containerColor = background,
         topBar = {
             TopAppBar(