Add some comments.

client/src/components/EditSongDialog.tsx

@@ -56,6 +56,10 @@ export default function EditSongDialog(props: IProps) {
                 />
             </Grid>
             <Grid item xs={12}>
+                { // TODO: this autocomplete is not controlled but does send updates to the parent
+                  // right away. In other words, there is no way to affect its value from outside
+                  // the dialog.
+                }
                 <Autocomplete
                     options={props.artists}
                     getOptionLabel={(option) => option.name as string}