Feature/v2/shared tool hooks (#4134)

# Description of Changes

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- What was changed
- Why the change was made
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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: Reece Browne <[email protected]>

CLAUDE.md

@@ -59,12 +59,73 @@ Frontend designed for **stateful document processing**:
 Without cleanup: browser crashes with memory leaks.
 
 #### Tool Development
-- **Pattern**: Follow `src/tools/Split.tsx` as reference implementation
-- **File Access**: Tools receive `selectedFiles` prop (computed from activeFiles based on user selection)
-- **File Selection**: Users select files in FileEditor (tool mode) → stored as IDs → computed to File objects for tools
-- **Integration**: All files are part of FileContext ecosystem - automatic memory management and operation tracking
-- **Parameters**: Tool parameter handling patterns still being standardized
-- **Preview Integration**: Tools can implement preview functionality (see Split tool's thumbnail preview)
+
+**Architecture**: Modular hook-based system with clear separation of concerns:
+
+- **useToolOperation** (`frontend/src/hooks/tools/shared/useToolOperation.ts`): Main orchestrator hook
+  - Coordinates all tool operations with consistent interface
+  - Integrates with FileContext for operation tracking
+  - Handles validation, error handling, and UI state management
+
+- **Supporting Hooks**:
+  - **useToolState**: UI state management (loading, progress, error, files)
+  - **useToolApiCalls**: HTTP requests and file processing
+  - **useToolResources**: Blob URLs, thumbnails, ZIP downloads
+
+- **Utilities**:
+  - **toolErrorHandler**: Standardized error extraction and i18n support
+  - **toolResponseProcessor**: API response handling (single/zip/custom)
+  - **toolOperationTracker**: FileContext integration utilities
+
+**Three Tool Patterns**:
+
+**Pattern 1: Single-File Tools** (Individual processing)
+- Backend processes one file per API call
+- Set `multiFileEndpoint: false`
+- Examples: Compress, Rotate
+```typescript
+return useToolOperation({
+  operationType: 'compress',
+  endpoint: '/api/v1/misc/compress-pdf',
+  buildFormData: (params, file: File) => { /* single file */ },
+  multiFileEndpoint: false,
+  filePrefix: 'compressed_'
+});
+```
+
+**Pattern 2: Multi-File Tools** (Batch processing)
+- Backend accepts `MultipartFile[]` arrays in single API call
+- Set `multiFileEndpoint: true`
+- Examples: Split, Merge, Overlay
+```typescript
+return useToolOperation({
+  operationType: 'split',
+  endpoint: '/api/v1/general/split-pages',
+  buildFormData: (params, files: File[]) => { /* all files */ },
+  multiFileEndpoint: true,
+  filePrefix: 'split_'
+});
+```
+
+**Pattern 3: Complex Tools** (Custom processing)
+- Tools with complex routing logic or non-standard processing
+- Provide `customProcessor` for full control
+- Examples: Convert, OCR
+```typescript
+return useToolOperation({
+  operationType: 'convert',
+  customProcessor: async (params, files) => { /* custom logic */ },
+  filePrefix: 'converted_'
+});
+```
+
+**Benefits**:
+- **No Timeouts**: Operations run until completion (supports 100GB+ files)
+- **Consistent**: All tools follow same pattern and interface  
+- **Maintainable**: Single responsibility hooks, easy to test and modify
+- **i18n Ready**: Built-in internationalization support
+- **Type Safe**: Full TypeScript support with generic interfaces
+- **Memory Safe**: Automatic resource cleanup and blob URL management
 
 ## Architecture Overview
 
@@ -126,7 +187,10 @@ Without cleanup: browser crashes with memory leaks.
 - **Core Status**: React SPA architecture complete with multi-tool workflow support
 - **State Management**: FileContext handles all file operations and tool navigation  
 - **File Processing**: Production-ready with memory management for large PDF workflows (up to 100GB+)
-- **Tool Integration**: Standardized tool interface - see `src/tools/Split.tsx` as reference
+- **Tool Integration**: Modular hook architecture with `useToolOperation` orchestrator
+  - Individual hooks: `useToolState`, `useToolApiCalls`, `useToolResources`
+  - Utilities: `toolErrorHandler`, `toolResponseProcessor`, `toolOperationTracker`
+  - Pattern: Each tool creates focused operation hook, UI consumes state/actions
 - **Preview System**: Tool results can be previewed without polluting file context (Split tool example)
 - **Performance**: Web Worker thumbnails, IndexedDB persistence, background processing
 
@@ -141,7 +205,7 @@ Without cleanup: browser crashes with memory leaks.
 - **Security**: When `DOCKER_ENABLE_SECURITY=false`, security-related classes are excluded from compilation
 - **FileContext**: All file operations MUST go through FileContext - never bypass with direct File handling
 - **Memory Management**: Manual cleanup required for PDF.js documents and blob URLs - don't remove cleanup code
-- **Tool Development**: New tools should follow Split tool pattern (`src/tools/Split.tsx`)
+- **Tool Development**: New tools should follow `useToolOperation` hook pattern (see `useCompressOperation.ts`)
 - **Performance Target**: Must handle PDFs up to 100GB+ without browser crashes
 - **Preview System**: Tools can preview results without polluting main file context (see Split tool implementation)