fix: always sync compiler dropdowns to redux state

Set the vscode-single-select value unconditionally in the sync effects so the dropdown reflects redux state even when the level is empty (e.g. transiently while switching projects), instead of keeping the previous project's selection.

Addresses PR review feedback on #1655.

Author: chagong

src/project-settings/assets/compiler/features/CompilerConfigurationView.tsx

@@ -111,19 +111,21 @@ const CompilerConfigurationView = (): JSX.Element | null => {
   useSelectChange(sourceRef, onChangeSourceLevel);
   useSelectChange(targetRef, onChangeTargetLevel);
 
-  // Keep the rendered selection in sync with the redux state.
+  // Keep the rendered selection in sync with the redux state. Set the value
+  // unconditionally (even when the level is "") so the dropdown always reflects
+  // state instead of keeping the previous project's selection.
   useEffect(() => {
-    if (complianceRef.current && complianceLevel) {
+    if (complianceRef.current) {
       (complianceRef.current as any).value = complianceLevel;
     }
   }, [complianceLevel, availableComplianceLevels]);
   useEffect(() => {
-    if (sourceRef.current && sourceLevel) {
+    if (sourceRef.current) {
       (sourceRef.current as any).value = sourceLevel;
     }
   }, [sourceLevel, availableComplianceLevels]);
   useEffect(() => {
-    if (targetRef.current && targetLevel) {
+    if (targetRef.current) {
       (targetRef.current as any).value = targetLevel;
     }
   }, [targetLevel, availableComplianceLevels]);