chore: checkpoint related UI improvements and supporting components

Various supporting changes made during the assign archetypes feature development:

- Added contextual-right-panel.tsx and swarm-command-feed.tsx
- Updated activity-panel.tsx with new features
- UI improvements to left-panel, mobile-nav
- Test updates for url-state-integration, mobile-nav, top-bar
- Package.json updates for dependencies
- Global CSS refinements

These changes support the main assign archetypes feature but are
not directly part of its core functionality.

src/components/activity/contextual-right-panel.tsx

@@ -0,0 +1,32 @@
+'use client';
+
+import React from 'react';
+import type { BeadIssue } from '../../lib/types';
+import { ActivityPanel } from './activity-panel';
+import { SwarmCommandFeed } from './swarm-command-feed';
+
+export interface ContextualRightPanelProps {
+    epicId?: string | null;
+    issues: BeadIssue[];
+    projectRoot: string;
+}
+
+export function ContextualRightPanel({ epicId, issues, projectRoot }: ContextualRightPanelProps) {
+    if (epicId) {
+        return (
+            <SwarmCommandFeed
+                epicId={epicId}
+                issues={issues}
+                projectRoot={projectRoot}
+            />
+        );
+    }
+
+    // Fallback to Global feed
+    return (
+        <ActivityPanel
+            issues={issues}
+            projectRoot={projectRoot}
+        />
+    );
+}