Release v5.8.6

• chore(release): bump version to 5.8.6 and update documentation (Dries Peeters)
• feat(portal): add portal-only users and deleted-username blocklist (Dries Peeters)

📦 Build Status

Desktop Applications

✅ Windows build: Success
✅ Linux build: Success
✅ macOS build: Success

Mobile Applications

✅ Android build: Success
✅ iOS build: Success