feat: Supports torrent engine in hydra GUI and CLI

[Leroy-X]

Preflight checklist

• I searched existing issues and this has not been proposed already.
• I checked the README and this is not already supported.

Component

Desktop GUI (Hydra Download Manager)

Problem

I'm so glad I discovered such an excellent downloader. I hope it can support magnet link downloads; that would make it even more amazing.

Thank you so much

Proposed solution

Supports magnet link downloads and torrent files; Trackers subscription is available.

Alternatives considered

No response

Platforms this should cover

• Linux
• macOS
• Windows
• Android / iOS (via libhydra)

Additional context

No response

Compatibility

• This changes existing behavior (flags, defaults, output format, or the C ABI).

Contribution

• I'm willing to open a pull request implementing this.