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/js/logic/pdf-booklet-page.ts

@@ -226,9 +226,9 @@ async function generatePreview() {
       const ctx = offscreen.getContext('2d')!;
 
       await page.render({
-        canvasContext: ctx as any,
+        canvasContext: ctx as unknown as CanvasRenderingContext2D,
         viewport: viewport,
-        canvas: offscreen as any,
+        canvas: offscreen as unknown as HTMLCanvasElement,
       }).promise;
 
       const bitmap = await createImageBitmap(offscreen);