Clean up Devolutions migration leftovers

[Marc-André Moreau (mamoreau-devolutions)]

Summary

• remove leftover issue template auto-assignees and old Tolgee automation from the repository
• update migrated repository references, security reporting, funding/support surfaces, and related workflows
• require an explicit version input in the release workflow instead of reading from source metadata
• fix the broken README supported package managers image and point the translation link at the correct wiki page

Testing

• Not run; changes are documentation, repository configuration, workflow, and UI cleanup only