feat: [US-056] - Character management UI in project settings

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/editor/Toolbar.tsx

@@ -7,6 +7,7 @@ type ToolbarProps = {
   onSave: () => void
   onExport: () => void
   onImport: () => void
+  onProjectSettings: () => void
 }
 
 export default function Toolbar({
@@ -16,6 +17,7 @@ export default function Toolbar({
   onSave,
   onExport,
   onImport,
+  onProjectSettings,
 }: ToolbarProps) {
   return (
     <div className="flex items-center justify-between border-b border-zinc-200 bg-zinc-50 px-4 py-2 dark:border-zinc-700 dark:bg-zinc-800">
@@ -44,6 +46,12 @@ export default function Toolbar({
       </div>
 
       <div className="flex items-center gap-2">
+        <button
+          onClick={onProjectSettings}
+          className="rounded border border-zinc-300 bg-white px-3 py-1.5 text-sm font-medium text-zinc-700 hover:bg-zinc-50 focus:outline-none focus:ring-2 focus:ring-blue-500 focus:ring-offset-2 dark:border-zinc-600 dark:bg-zinc-700 dark:text-zinc-200 dark:hover:bg-zinc-600 dark:focus:ring-offset-zinc-800"
+        >
+          Project Settings
+        </button>
         <button
           onClick={onSave}
           className="rounded border border-zinc-300 bg-white px-3 py-1.5 text-sm font-medium text-zinc-700 hover:bg-zinc-50 focus:outline-none focus:ring-2 focus:ring-blue-500 focus:ring-offset-2 dark:border-zinc-600 dark:bg-zinc-700 dark:text-zinc-200 dark:hover:bg-zinc-600 dark:focus:ring-offset-zinc-800"