Version 6 Matrix rooms silently fail on permission-restricted actions

[SpookySkeletons]

Describe the bug

Version 6 (v6) Matrix rooms do not surface any errors when encountering permission issues with invites or joining. Instead, the UI will indefinitely show a loading/spinner state as if the action is in progress. The spinner persists until the user navigates away and back, at which point no error or feedback is shown.

This likely indicates that Commet's room permission handling does not account for older room versions.

To Reproduce

1. Attempt to join or be invited to a v6 Matrix room where permissions would restrict the action
2. Observe the UI spinning/loading indefinitely
3. Click away from the room and return
4. Note no error message is ever displayed

Expected behavior

The client should return a clear error message when a permission-restricted action fails, regardless of room version.

Screenshots

If applicable, add screenshots to help explain your problem.

Additional context

Issue appears specific to older room versions (v6 observed). Modern room versions may handle permissions correctly or good defaults have made the experience reasonably smooth. Worth auditing permission handling across all supported room versions.