Two-column bookmark manager with connect-on-startup

Replace the modal add/edit form with a master/detail dialog: bookmark
list on the left, the selected bookmark's settings on the right. Edits
are flushed back into the bookmark when the selection changes or the
dialog closes.

Bookmarks gain a "connect on startup" flag (only one at a time, since
the client holds a single connection); MainFrame connects to it once
the window is up.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

ts3-client/swing/src/main/java/com/ts3client/ui/IdentityChooser.java

@@ -17,16 +17,16 @@ final class IdentityChooser extends JComboBox<Object> {
 
     private static final String USE_DEFAULT = "‹Default identity›";
 
+    private final IdentityStore identities;
+    private final boolean allowDefault;
+
     IdentityChooser(IdentityStore identities, boolean allowDefault, String selectedId) {
+        this.identities = identities;
+        this.allowDefault = allowDefault;
         if (allowDefault) addItem(USE_DEFAULT);
         for (IdentityEntry e : identities.all()) addItem(e);
 
-        IdentityEntry selected = identities.byId(selectedId);
-        if (selected != null) {
-            setSelectedItem(selected);
-        } else if (allowDefault) {
-            setSelectedItem(USE_DEFAULT);
-        }
+        setSelectedIdentityId(selectedId);
 
         setRenderer(new DefaultListCellRenderer() {
             @Override
@@ -45,4 +45,14 @@ final class IdentityChooser extends JComboBox<Object> {
         Object v = getSelectedItem();
         return v instanceof IdentityEntry ? ((IdentityEntry) v).getId() : "";
     }
+
+    /** Selects the identity with the given id, falling back to the default entry. */
+    void setSelectedIdentityId(String id) {
+        IdentityEntry selected = identities.byId(id);
+        if (selected != null) {
+            setSelectedItem(selected);
+        } else if (allowDefault) {
+            setSelectedItem(USE_DEFAULT);
+        }
+    }
 }