[Bug] After creating a community, app lands on "Join a community" and I can't get in

## Summary

I successfully **created** a community, but the desktop app still shows the **Join a community** screen and I cannot enter the community I just made. There is no obvious path from \"created\" → \"I'm inside my community.\"

## Screenshot

App is stuck on:

- Title: **Join a community**
- Subtitle: *Enter the invite link or community…*
- Input placeholder: *Invite link or community…*
- Helper text: *Joining a private community? Some communities need the owner to add you… ID and send it to the community owner.*

(I can attach the full screenshot in a follow-up comment if GitHub CLI didn't preserve it.)

## Expected

After creating a community (as the owner/creator), I should land **inside** that community automatically — or at least see a clear next step like \"Open my community\" / the community URL / claim confirmation, not a blank join form that implies I need an invite to a place I just created.

## Actual

Creation appears to succeed (or at least complete the create flow), then I'm dropped on **Join a community** with only:

1. invite link / community ID input
2. private-community owner-add messaging

I don't have an invite link for my own community, and the UI doesn't surface my community ID / URL after create, so I'm stuck outside.

## Steps to reproduce

1. Install / open Buzz Desktop (OSS build).
2. Go through **Create a community** (hosted / Builderlab path).
3. Finish create / claim flow.
4. Return to the app.

**Result:** \"Join a community\" screen; cannot enter the community just created.

## Environment

- Client: Buzz Desktop (screenshot UI matches current onboarding join screen)
- Path: create community → back in app → join screen
- OS: macOS (happy to fill exact app version if needed)

## Related

Adjacent onboarding friction (not the same bug, but same funnel):

- #2276 Reduce steps to create a community
- #2312 Onboarding: 'Create a community' needs an explanation layer

## Ask

Please treat this as a **post-create handoff bug**: creator should auto-join / auto-open their community, or the create success UI should give a copyable community URL/ID and a one-tap \"Enter community\" action.

Happy to provide more logs / exact version / another screenshot if useful.