Add undo/redo functionality and refactor signature settings UI

- Introduced HistoryAPIBridge for managing undo/redo actions.
- Updated SignSettings component to include undo/redo buttons.
- Refactored signature type selection to use Tabs for better UI.
- Enhanced SignatureAPIBridge to store image data for annotations.
- Integrated history management into SignatureContext for state handling.

frontend/src/components/viewer/HistoryAPIBridge.tsx

@@ -0,0 +1,86 @@
+import React, { useImperativeHandle, forwardRef, useEffect } from 'react';
+import { useHistoryCapability } from '@embedpdf/plugin-history/react';
+import { useAnnotationCapability } from '@embedpdf/plugin-annotation/react';
+import { useSignature } from '../../contexts/SignatureContext';
+
+export interface HistoryAPI {
+  undo: () => void;
+  redo: () => void;
+  canUndo: () => boolean;
+  canRedo: () => boolean;
+}
+
+export interface HistoryAPIBridgeProps {}
+
+export const HistoryAPIBridge = forwardRef<HistoryAPI, HistoryAPIBridgeProps>((props, ref) => {
+  const { provides: historyApi } = useHistoryCapability();
+  const { provides: annotationApi } = useAnnotationCapability();
+  const { getImageData } = useSignature();
+
+
+  useImperativeHandle(ref, () => ({
+    undo: () => {
+      if (historyApi) {
+        historyApi.undo();
+
+        // Restore image data for STAMP annotations after undo
+        setTimeout(() => {
+          if (!annotationApi) return;
+
+          for (let pageIndex = 0; pageIndex < 10; pageIndex++) {
+            const pageAnnotationsTask = annotationApi.getPageAnnotations?.({ pageIndex });
+            if (pageAnnotationsTask) {
+              pageAnnotationsTask.toPromise().then((pageAnnotations: any) => {
+                if (pageAnnotations) {
+                  pageAnnotations.forEach((ann: any) => {
+                    if (ann.type === 13) {
+                      const storedImageData = getImageData(ann.id);
+
+                      if (storedImageData && (!ann.imageSrc || ann.imageSrc !== storedImageData)) {
+                        const originalData = {
+                          type: ann.type,
+                          rect: ann.rect,
+                          author: ann.author || 'Digital Signature',
+                          subject: ann.subject || 'Digital Signature',
+                          pageIndex: pageIndex,
+                          id: ann.id,
+                          created: ann.created || new Date(),
+                          imageSrc: storedImageData
+                        };
+
+                        annotationApi.deleteAnnotation(pageIndex, ann.id);
+                        setTimeout(() => {
+                          annotationApi.createAnnotation(pageIndex, originalData);
+                        }, 50);
+                      }
+                    }
+                  });
+                }
+              }).catch((error: any) => {
+                console.error(`Failed to get annotations for page ${pageIndex}:`, error);
+              });
+            }
+          }
+        }, 200);
+      }
+    },
+
+    redo: () => {
+      if (historyApi) {
+        historyApi.redo();
+      }
+    },
+
+    canUndo: () => {
+      return historyApi ? historyApi.canUndo() : false;
+    },
+
+    canRedo: () => {
+      return historyApi ? historyApi.canRedo() : false;
+    },
+  }), [historyApi]);
+
+  return null; // This is a bridge component with no UI
+});
+
+HistoryAPIBridge.displayName = 'HistoryAPIBridge';