### CHANGES
- Add `.browserslistrc` to define target browser versions.
- Upgrade `pdfjs-dist` dependency from v2.16 to v4.2.67.
- Upgrade `nanoid` dependency from v4.0.2 to v5.0.9.
- Introduce `pdf-config.ts` for centralized PDF.js worker setup.
- Refactor `PdfConversionService` to use new PDF worker configuration.
- Add static `pdf.worker.min.mjs` to serve PDF.js worker.
- Update Vite configuration for ESNext build target and PDF.js.
## CHANGES
- add new aot.json for Atom-of-Thought (AoT) prompting
- define AoT strategy description and detailed prompt instructions
- update strategies.json to include AoT in available strategies list
- ensure AoT strategy appears alongside CoD, CoT, and LTM options
