Feature/viewer annotation toggle (#4557)

# Description of Changes

<!--
Please provide a summary of the changes, including:

- What was changed
- Why the change was made
- Any challenges encountered

Closes #(issue_number)
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---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

---------

Co-authored-by: Copilot <[email protected]>
Co-authored-by: James Brunton <[email protected]>

frontend/src/contexts/ViewerContext.tsx

@@ -123,6 +123,15 @@ interface ViewerContextType {
   isThumbnailSidebarVisible: boolean;
   toggleThumbnailSidebar: () => void;
 
+  // Annotation visibility toggle
+  isAnnotationsVisible: boolean;
+  toggleAnnotationsVisibility: () => void;
+
+  // Annotation/drawing mode for viewer
+  isAnnotationMode: boolean;
+  setAnnotationMode: (enabled: boolean) => void;
+  toggleAnnotationMode: () => void;
+
   // State getters - read current state from bridges
   getScrollState: () => ScrollState;
   getZoomState: () => ZoomState;
@@ -208,6 +217,8 @@ interface ViewerProviderProps {
 export const ViewerProvider: React.FC<ViewerProviderProps> = ({ children }) => {
   // UI state - only state directly managed by this context
   const [isThumbnailSidebarVisible, setIsThumbnailSidebarVisible] = useState(false);
+  const [isAnnotationsVisible, setIsAnnotationsVisible] = useState(true);
+  const [isAnnotationMode, setIsAnnotationModeState] = useState(false);
 
   // Get current navigation state to check if we're in sign mode
   useNavigation();
@@ -268,6 +279,18 @@ export const ViewerProvider: React.FC<ViewerProviderProps> = ({ children }) => {
     setIsThumbnailSidebarVisible(prev => !prev);
   };
 
+  const toggleAnnotationsVisibility = () => {
+    setIsAnnotationsVisible(prev => !prev);
+  };
+
+  const setAnnotationMode = (enabled: boolean) => {
+    setIsAnnotationModeState(enabled);
+  };
+
+  const toggleAnnotationMode = () => {
+    setIsAnnotationModeState(prev => !prev);
+  };
+
   // State getters - read from bridge refs
   const getScrollState = (): ScrollState => {
     return bridgeRefs.current.scroll?.state || { currentPage: 1, totalPages: 0 };
@@ -547,6 +570,13 @@ export const ViewerProvider: React.FC<ViewerProviderProps> = ({ children }) => {
     isThumbnailSidebarVisible,
     toggleThumbnailSidebar,
 
+    // Annotation controls
+    isAnnotationsVisible,
+    toggleAnnotationsVisibility,
+    isAnnotationMode,
+    setAnnotationMode,
+    toggleAnnotationMode,
+
     // State getters
     getScrollState,
     getZoomState,

frontend/src/contexts/file/fileActions.ts

@@ -476,7 +476,6 @@ export async function addStirlingFileStubs(
   await addFilesMutex.lock();
 
   try {
-    if (DEBUG) console.log(`📄 addStirlingFileStubs: Adding ${stirlingFileStubs.length} StirlingFileStubs preserving metadata`);
 
     const existingQuickKeys = buildQuickKeySet(stateRef.current.files.byId);
     const validStubs: StirlingFileStub[] = [];
@@ -515,14 +514,12 @@ export async function addStirlingFileStubs(
                                 record.processedFile.totalPages !== record.processedFile.pages.length;
 
         if (needsProcessing) {
-          if (DEBUG) console.log(`📄 addStirlingFileStubs: Regenerating processedFile for ${record.name}`);
 
           // Use centralized metadata generation function
           const processedFileMetadata = await generateProcessedFileMetadata(stirlingFile);
           if (processedFileMetadata) {
             record.processedFile = processedFileMetadata;
             record.thumbnailUrl = processedFileMetadata.thumbnailUrl; // Update thumbnail if needed
-            if (DEBUG) console.log(`📄 addStirlingFileStubs: Regenerated processedFile for ${record.name} with ${processedFileMetadata.totalPages} pages`);
           } else {
             // Fallback for files that couldn't be processed
             if (DEBUG) console.warn(`📄 addStirlingFileStubs: Failed to regenerate processedFile for ${record.name}`);
@@ -541,7 +538,6 @@ export async function addStirlingFileStubs(
     // Dispatch ADD_FILES action if we have new files
     if (validStubs.length > 0) {
       dispatch({ type: 'ADD_FILES', payload: { stirlingFileStubs: validStubs } });
-      if (DEBUG) console.log(`📄 addStirlingFileStubs: Successfully added ${validStubs.length} files with preserved metadata`);
     }
 
     return loadedFiles;