v0.7.5

Release post: https://mau.fi/blog/2025-07-mautrix-release/

• Fixed federation key response when using direct media.
• Changed prefix_webhook_messages option to generate MSC4144 fallbacks, so that any compatible clients will hide the prefix.
• Changed new room creation to hardcode room v11 to avoid v12 rooms being created before proper support for them can be added.