- Implemented custom HTML templates for `400`, `404`, `500`, and `525` error pages with multilingual support.
- Added embedded file system for error page templates and assets.
- Introduced fallback mechanism to serve minimal plain text for missing error templates.
- Integrated TailwindCSS for styling error pages, with a build script in `package.json`.
- Added `TARGETOS` and `TARGETARCH` arguments for multi-architecture build support.
- Updated build commands to utilize the provided OS/ARCH arguments.
- Simplified Dockerfile by removing redundant conditional logic for `go.sum`.