refactor(translations): move Help translate into the App language page

Per review, it shouldn't be a top-level Settings entry: the "Help translate"
link now sits at the top of the full-screen App language picker (OptionPicker
gains an optional header slot). Updated README + changelog wording to match.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/src/main/java/de/jeanlucmakiola/calendula/ui/common/Picker.kt

@@ -86,8 +86,10 @@ fun <T> OptionPicker(
     label: @Composable (T) -> String,
     onSelect: (T) -> Unit,
     onDismiss: () -> Unit,
+    header: (@Composable ColumnScope.() -> Unit)? = null,
 ) {
     FullScreenPicker(title = title, onDismiss = onDismiss) {
+        header?.invoke(this)
         options.forEachIndexed { index, option ->
             val isSelected = option == selected
             GroupedRow(

app/src/main/java/de/jeanlucmakiola/calendula/ui/settings/SettingsScreen.kt

@@ -224,7 +224,6 @@ private fun SettingsHub(
             onClick = onManageCalendars,
         )
         LanguageRow(position = Position.Middle)
-        HelpTranslateRow(position = Position.Middle)
         // One-tap add of the "New event" Quick Settings tile. The system prompt
         // is API 33+; on older versions the tile is still addable manually from
         // the QS editor, so the row simply doesn't appear here.
@@ -290,20 +289,6 @@ private fun QuickSettingsTileRow(position: Position) {
     )
 }
 
-/** Opens the project's Weblate engage page so users can contribute translations. */
-@Composable
-private fun HelpTranslateRow(position: Position) {
-    val context = LocalContext.current
-    val url = stringResource(R.string.about_translate_url)
-    GroupedRow(
-        title = stringResource(R.string.settings_translate),
-        summary = stringResource(R.string.settings_translate_hint),
-        position = position,
-        leading = { CategoryIcon(Icons.Default.Translate, ChipAccent.Neutral) },
-        onClick = { openUrl(context, url) },
-    )
-}
-
 @Composable
 private fun LanguageRow(position: Position) {
     val context = LocalContext.current
@@ -334,6 +319,18 @@ private fun LanguageRow(position: Position) {
                 AppLanguage.apply(it)
             },
             onDismiss = { showDialog = false },
+            // Invite contributions right where users pick their language.
+            header = {
+                val translateUrl = stringResource(R.string.about_translate_url)
+                GroupedRow(
+                    title = stringResource(R.string.settings_translate),
+                    summary = stringResource(R.string.settings_translate_hint),
+                    position = Position.Alone,
+                    leading = { CategoryIcon(Icons.Default.Translate, ChipAccent.Neutral) },
+                    onClick = { openUrl(context, translateUrl) },
+                )
+                Spacer(Modifier.height(16.dp))
+            },
         )
     }
 }