feat: integrate Tesseract.js with improved language availability and font handling

- Refactored OCR page recognition to utilize a configured Tesseract worker.
- Added functions to manage font URLs and asset filenames based on language.
- Implemented language availability checks and error handling for unsupported languages.
- Enhanced PDF workflow to display available OCR languages and handle user selections.
- Introduced utility functions for resolving Tesseract asset configurations.
- Added tests for OCR functionality, font loading, and Tesseract runtime behavior.
- Updated global types to include environment variables for Tesseract and font configurations.

src/types/globals.d.ts

@@ -1 +1,15 @@
+/// <reference types="vite/client" />
+
+interface ImportMetaEnv {
+  readonly VITE_TESSERACT_WORKER_URL?: string;
+  readonly VITE_TESSERACT_CORE_URL?: string;
+  readonly VITE_TESSERACT_LANG_URL?: string;
+  readonly VITE_TESSERACT_AVAILABLE_LANGUAGES?: string;
+  readonly VITE_OCR_FONT_BASE_URL?: string;
+}
+
+interface ImportMeta {
+  readonly env: ImportMetaEnv;
+}
+
 declare const __SIMPLE_MODE__: boolean;