refactor: migrate codebase from CommonJS (.js) to ES modules (.mjs)}
- Rename all .js files to .mjs across bin, src, electron, lib, and strings - Convert require()/module.exports to import/export syntax throughout - Update package.json entry points and dependencies for ESM compatibility - Simplify menu creation logic in electron module - Update HTML script reference to use .mjs extension - Update README and change-log with migration notes - Refresh yarn.lock with updated dependencies