feat: add integrated terminal with tab system and theme support

- Add terminal view with draggable split panels and multi-tab support
- Implement terminal WebSocket server with password protection
- Add per-terminal font size that persists when moving between tabs
- Support all 12 app themes with matching terminal colors
- Add keyboard shortcut (Ctrl+`) to toggle terminal view
- Include scrollback buffer for session history on reconnect

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

apps/app/src/components/layout/sidebar.tsx

@@ -609,6 +609,12 @@ export function Sidebar() {
           icon: UserCircle,
           shortcut: shortcuts.profiles,
         },
+        {
+          id: "terminal",
+          label: "Terminal",
+          icon: Terminal,
+          shortcut: shortcuts.terminal,
+        },
       ],
     },
   ];