SearchBar: adopt outside text changes in a side effect

SearchBar keeps a TextFieldValue so that the cursor ends up behind text that was
changed from the outside (a search started by typing on a physical keyboard, or
a reset search). That value was updated during composition, which is an
anti-pattern: the value read earlier in the same composition is what gets drawn,
so the write only schedules another recomposition pass of the search bar - and
it can be dropped entirely if the composition does not complete.

Do the same update in a SideEffect, after the composition. No behaviour change
for the user.

app/ui/src/main/java/de/mm20/launcher2/ui/component/SearchBar.kt

@@ -24,6 +24,7 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.SideEffect
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
@@ -143,8 +144,14 @@ fun SearchBar(
     val textFieldValue = remember {
         mutableStateOf(TextFieldValue(value, TextRange(value.length)))
     }
-    if (textFieldValue.value.text != value) {
-        textFieldValue.value = TextFieldValue(value, TextRange(value.length))
+    // Characters the user typed are already in this value; onValueChange below keeps the cursor
+    // where the user put it. Text that changed from the outside - the search was reset, or a
+    // character was inserted by the physical keyboard handler - is adopted here, with the cursor at
+    // the end. This must not write state during composition, so it runs in a side effect after it.
+    SideEffect {
+        if (textFieldValue.value.text != value) {
+            textFieldValue.value = TextFieldValue(value, TextRange(value.length))
+        }
     }
 
     LauncherCard(