Refactor and enhance type safety across various modules

- Updated function parameters and return types in `page-preview.ts`, `pdf-decrypt.ts`, and `pymupdf-loader.ts` for improved type safety.
- Introduced type definitions for `CpdfInstance`, `PyMuPDFInstance`, and other related types to ensure better type checking.
- Enhanced error handling in `sanitize.ts` by creating a utility function for error messages.
- Removed unnecessary type assertions and improved type inference in `editor.ts`, `serialization.ts`, and `tools.test.ts`.
- Added type definitions for markdown-it plugins to improve compatibility and type safety.
- Enforced stricter TypeScript settings by enabling `noImplicitAny` in `tsconfig.json`.
- Cleaned up test files by refining type assertions and ensuring consistency in type usage.

src/tests/tools.test.ts

@@ -23,10 +23,12 @@ describe('Tool Categories Configuration', () => {
     // **KEY CHANGE**: This test now ensures IDs are unique only WITHIN this specific category.
     it('should not contain any duplicate tool IDs within its own list', () => {
       const toolIds = category.tools.map((tool) => {
-        if ('id' in tool) return (tool as any).id;
+        if ('id' in tool) return tool.id;
         if ('href' in tool) {
-          const match = (tool as any).href.match(/\/([^/]+)\.html$/);
-          return match ? match[1] : (tool as any).href;
+          const match = (tool as { href: string }).href.match(
+            /\/([^/]+)\.html$/
+          );
+          return match ? match[1] : (tool as { href: string }).href;
         }
         return 'unknown';
       });