feat: add Terminal component and styles

- Introduced a new Terminal component for embedding a terminal interface within the application.
- Added corresponding styles in Terminal.scss to ensure proper layout and appearance.
- Updated index.ts to export the Terminal component for accessibility within the module.

Author: atyrode

src/frontend/src/pad/containers/Terminal.scss

@@ -0,0 +1,18 @@
+.terminal-container {
+  width: 100%;
+  height: 100%;
+  display: flex;
+  flex-direction: column;
+  overflow: hidden;
+}
+
+.terminal-iframe {
+  flex: 1;
+  background-color: #1e1e1e;
+  height: 100%;
+  width: 100%;
+  border: 0px !important;
+  overflow: hidden;
+  border-bottom-left-radius: var(--embeddable-radius);
+  border-bottom-right-radius: var(--embeddable-radius);
+}

src/frontend/src/pad/containers/Terminal.tsx

@@ -0,0 +1,41 @@
+import React from 'react';
+import { useWorkspaceState } from '../../api/hooks';
+import type { NonDeleted, ExcalidrawEmbeddableElement } from '@atyrode/excalidraw/element/types';
+import type { AppState } from '@atyrode/excalidraw/types';
+import './Terminal.scss';
+
+interface TerminalProps {
+  element: NonDeleted<ExcalidrawEmbeddableElement>;
+  appState: AppState;
+  excalidrawAPI?: any;
+}
+
+export const Terminal: React.FC<TerminalProps> = ({
+  element,
+  appState,
+  excalidrawAPI
+}) => {
+  const { data: workspaceState } = useWorkspaceState();
+  
+  const getTerminalUrl = () => {
+    if (!workspaceState) {
+      return 'https://terminal.example.dev';
+    }
+    
+    return `${workspaceState.base_url}/@${workspaceState.username}/${workspaceState.workspace_id}.${workspaceState.agent}/terminal`;
+  };
+
+  const terminalUrl = getTerminalUrl();
+
+  return (
+    <div className="terminal-container">
+      <iframe 
+        className="terminal-iframe" 
+        src={terminalUrl} 
+        title="Terminal"
+      />
+    </div>
+  );
+};
+
+export default Terminal;

src/frontend/src/pad/index.ts

@@ -2,10 +2,12 @@
 export * from './controls/ControlButton';
 export * from './controls/StateIndicator';
 export * from './containers/Dashboard';
+export * from './containers/Terminal';
 export * from './buttons';
 export * from './editors';
 
 // Default exports
 export { default as ControlButton } from './controls/ControlButton';
 export { default as StateIndicator } from './controls/StateIndicator';
 export { default as Dashboard } from './containers/Dashboard';
+export { default as Terminal } from './containers/Terminal';