Feature/v2/multiselect (#4024)

# Description of Changes
This pull request introduces significant updates to the file selection
logic, tool rendering, and file context management in the frontend
codebase. The changes aim to improve modularity, enhance
maintainability, and streamline the handling of file-related operations.
Key updates include the introduction of a new `FileSelectionContext`,
refactoring of file selection logic, and updates to tool management and
rendering.

### File Selection Context and Logic Refactor:
* Added a new `FileSelectionContext` to centralize file selection state
and provide utility hooks for managing selected files, selection limits,
and tool mode. (`frontend/src/contexts/FileSelectionContext.tsx`,
[frontend/src/contexts/FileSelectionContext.tsxR1-R77](diffhunk://#diff-bda35f1aaa5eafa0a0dc48e0b1270d862f6da360ba1241234e891f0ca8907327R1-R77))
* Replaced local file selection logic in `FileEditor` with context-based
logic, improving consistency and reducing duplication.
(`frontend/src/components/fileEditor/FileEditor.tsx`,
[[1]](diffhunk://#diff-481d0a2d8a1714d34d21181db63a020b08dfccfbfa80bf47ac9af382dff25310R63-R70)
[[2]](diffhunk://#diff-481d0a2d8a1714d34d21181db63a020b08dfccfbfa80bf47ac9af382dff25310R404-R438)

### Tool Management and Rendering:
* Refactored `ToolRenderer` to use a `Suspense` fallback for lazy-loaded
tools, improving user experience during tool loading.
(`frontend/src/components/tools/ToolRenderer.tsx`,
[frontend/src/components/tools/ToolRenderer.tsxL32-L64](diffhunk://#diff-2083701113aa92cd1f5ce1b4b52cc233858e31ed7bcf39c5bfb1bcc34e99b6a9L32-L64))
* Simplified `ToolPicker` by reusing the `ToolRegistry` type, reducing
redundancy. (`frontend/src/components/tools/ToolPicker.tsx`,
[frontend/src/components/tools/ToolPicker.tsxL4-R4](diffhunk://#diff-e47deca9132018344c159925f1264794acdd57f4b65e582eb9b2a4ea69ec126dL4-R4))

### File Context Enhancements:
* Introduced a utility function `getFileId` for consistent file ID
extraction, replacing repetitive inline logic.
(`frontend/src/contexts/FileContext.tsx`,
[[1]](diffhunk://#diff-95b3d103fa434f81fdae55f2ea14eda705f0def45a0f2c5754f81de6f2fd93bcR25)
[[2]](diffhunk://#diff-95b3d103fa434f81fdae55f2ea14eda705f0def45a0f2c5754f81de6f2fd93bcL101-R102)
* Updated `FileContextProvider` to use more specific types for PDF
documents, enhancing type safety.
(`frontend/src/contexts/FileContext.tsx`,
[[1]](diffhunk://#diff-95b3d103fa434f81fdae55f2ea14eda705f0def45a0f2c5754f81de6f2fd93bcL350-R351)
[[2]](diffhunk://#diff-95b3d103fa434f81fdae55f2ea14eda705f0def45a0f2c5754f81de6f2fd93bcL384-R385)

### Compression Tool Enhancements:
* Added blob URL cleanup logic to the compression hook to prevent memory
leaks. (`frontend/src/hooks/tools/compress/useCompressOperation.ts`,
[frontend/src/hooks/tools/compress/useCompressOperation.tsR58-L66](diffhunk://#diff-d7815fea0e89989511ae1786f7031cba492b9f2db39b7ade92d9736d1bd4b673R58-L66))
* Adjusted file ID generation in the compression operation to handle
multiple files more effectively.
(`frontend/src/hooks/tools/compress/useCompressOperation.ts`,
[frontend/src/hooks/tools/compress/useCompressOperation.tsL90-R102](diffhunk://#diff-d7815fea0e89989511ae1786f7031cba492b9f2db39b7ade92d9736d1bd4b673L90-R102))

---

## 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.

frontend/src/types/pageEditor.ts

@@ -36,3 +36,19 @@ export interface UndoRedoState {
   operations: PageOperation[];
   currentIndex: number;
 }
+
+export interface PageEditorFunctions {
+  closePdf: () => void;
+  handleUndo: () => void;
+  handleRedo: () => void;
+  canUndo: boolean;
+  canRedo: boolean;
+  handleRotate: () => void;
+  handleDelete: () => void;
+  handleSplit: () => void;
+  onExportSelected: () => void;
+  onExportAll: () => void;
+  exportLoading: boolean;
+  selectionMode: boolean;
+  selectedPages: number[];
+}

frontend/src/types/tool.ts

@@ -0,0 +1,73 @@
+import React from 'react';
+
+export type MaxFiles = number; // 1=single, >1=limited, -1=unlimited
+export type ToolCategory = 'manipulation' | 'conversion' | 'analysis' | 'utility' | 'optimization' | 'security';
+export type ToolDefinition = Omit<Tool, 'name'>;
+export type ToolStepType = 'files' | 'settings' | 'results';
+
+export interface BaseToolProps {
+  onComplete?: (results: File[]) => void;
+  onError?: (error: string) => void;
+  onPreviewFile?: (file: File | null) => void;
+}
+
+export interface ToolStepConfig {
+  type: ToolStepType;
+  title: string;
+  isVisible: boolean;
+  isCompleted: boolean;
+  isCollapsed?: boolean;
+  completedMessage?: string;
+  onCollapsedClick?: () => void;
+}
+
+export interface ToolValidationResult {
+  valid: boolean;
+  errors?: string[];
+  warnings?: string[];
+}
+
+export interface ToolResult {
+  success: boolean;
+  files?: File[];
+  error?: string;
+  downloadUrl?: string;
+  metadata?: Record<string, any>;
+}
+
+export interface Tool {
+  id: string;
+  name: string;
+  icon: React.ReactNode;
+  component: React.ComponentType<BaseToolProps>;
+  maxFiles: MaxFiles;
+  category?: ToolCategory;
+  description?: string;
+  endpoints?: string[];
+  supportedFormats?: string[];
+  validation?: (files: File[]) => ToolValidationResult;
+}
+
+export type ToolRegistry = Record<string, Tool>;
+
+export interface FileSelectionState {
+  selectedFiles: File[];
+  maxFiles: MaxFiles;
+  isToolMode: boolean;
+}
+
+export interface FileSelectionActions {
+  setSelectedFiles: (files: File[]) => void;
+  setMaxFiles: (maxFiles: MaxFiles) => void;
+  setIsToolMode: (isToolMode: boolean) => void;
+  clearSelection: () => void;
+}
+
+export interface FileSelectionComputed {
+  canSelectMore: boolean;
+  isAtLimit: boolean;
+  selectionCount: number;
+  isMultiFileMode: boolean;
+}
+
+export interface FileSelectionContextValue extends FileSelectionState, FileSelectionActions, FileSelectionComputed {}