feat(chat): integrate Epic 2, 3, 4 widgets into chat interface

- Create 5 widget wrappers for inline chat display:
  * WhaleActivityWidget - Wraps WhaleActivityFeed for whale transaction display
  * TradingSuggestionWidget - Wraps TradingSuggestionPanel for entry/exit suggestions
  * PortfolioWidget - Wraps PortfolioPanel for portfolio tracking
  * ChartCaptureWidget - Wraps ChartCapturePanel for chart screenshots
  * ThreadGeneratorWidget - Wraps ThreadGeneratorPanel for Twitter threads

- Update widgets/index.ts to export new widgets with Epic grouping

- Update ChatMessages.tsx:
  * Add 5 new widget types to MessageWidget union
  * Import new widget components and their types
  * Add renderWidget cases for all new widgets with proper callbacks
  * Update component documentation to list all supported widgets

- Widget integration pattern:
  * Widgets wrap panels in containers with consistent styling
  * All widgets support callback props for user interactions
  * Widgets can be embedded inline in assistant messages
  * Widget actions are handled via onWidgetAction callback

Enables AI to display Epic 2, 3, 4 panels inline in chat conversations

surfsense_browser_extension/sidepanel/widgets/WhaleActivityWidget.tsx

@@ -0,0 +1,31 @@
+import { WhaleActivityFeed, type WhaleTransaction } from "../whale/WhaleActivityFeed";
+
+export interface WhaleActivityWidgetProps {
+    /** List of whale transactions */
+    transactions: WhaleTransaction[];
+    /** Callback when a wallet is tracked */
+    onTrackWallet?: (address: string) => void;
+    /** Callback when a transaction is viewed */
+    onViewTransaction?: (txHash: string) => void;
+}
+
+/**
+ * WhaleActivityWidget - Inline whale activity display in chat
+ * Wraps WhaleActivityFeed for conversational UX
+ */
+export function WhaleActivityWidget({
+    transactions,
+    onTrackWallet,
+    onViewTransaction,
+}: WhaleActivityWidgetProps) {
+    return (
+        <div className="my-3">
+            <WhaleActivityFeed
+                transactions={transactions}
+                onTrackWallet={onTrackWallet}
+                onViewTransaction={onViewTransaction}
+            />
+        </div>
+    );
+}
+