Add Premiumize debrid provider

[ALenfant]

📌 Description

• Adds Premiumize as a supported debrid provider, including
  • Magnet/torrent submission
  • Transfer sync
  • File discovery
  • Download-link resolution
  • Account info
  • Cache checks
  • Speed tests
  • Cleanup

Fixes #81

---

Target Branch Check (IMPORTANT)

• I confirm this PR is targeting the correct branch

Expected target:

• beta (for features)

---

Changes Made

• Implemented the Premiumize provider using the official Premiumize API.
• Wired Premiumize into provider creation, setup/config UI, generated assets, and documentation.
• Added handling for Premiumize folder transfers, including recursive folder listing and a readiness guard for transfers marked finished before linked files are available.

---

Testing

• Tested locally

Steps:

1. Ran Decypharr locally with a Premiumize-only config and verified account/profile, cache check, speed test, transfer list/status, link resolution, and cleanup.
2. Completed a full Premiumize download using a legal Linux ISO magnet; verified local file size matched expected size.
3. Tested .torrent upload with the Ubuntu torrent fixture, flat multi-file folder handling with another test torrent, and nested folder handling with a third test torrent containing subfolders.

---

Risks / Notes

• Premiumize can briefly mark transfers finished before folder/file links are ready; the provider keeps those transfers active until linked files are visible.
• No config migration required.

---

Screenshots (if applicable)

---

Checklist

• Code builds successfully
• No console/log errors
• Reviewed my own code
• Target branch is correct