Bug: Invite / Relay Access UI is missing for self-hosted communities

### Describe the issue

I'm testing Buzz v0.5.3 with a self-hosted relay deployed using the official Hostinger Docker template.

The relay functions correctly:

- I can connect using the relay URL.
- Authentication succeeds.
- I can create channels.
- I can send messages.
- Relay owner is configured correctly.
- Relay admin is configured correctly.

However, the desktop application never exposes the Invite / Relay Access UI that exists for Builderlab-hosted communities.

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### Steps to reproduce

1. Deploy Buzz using the Hostinger Docker template.
2. Configure the relay owner.
3. Join the relay from Buzz Desktop using:
"I already have a community"
4. Enter the relay URL.
5. Open Settings.

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### Expected behavior

The relay owner should have access to the same community management features available on Builderlab-hosted communities, including:

- Invite users
- Relay access management
- Invite link generation (or equivalent)

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### Actual behavior

The self-hosted relay works normally, but there is no Invite or Relay Access section anywhere in the UI.

Builderlab-hosted communities immediately show the Invite section.

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### What I verified

Relay URL:
wss://

Relay owner configured:

RELAY_OWNER_PUBKEY=

Relay logs:

Relay owner bootstrapped

NIP-42 auth successful

Current relay configuration:

BUZZ_REQUIRE_AUTH_TOKEN=true

BUZZ_REQUIRE_RELAY_MEMBERSHIP=false

The relay contains the admin web configuration:

BUZZ_ADMIN_WEB_DIR
BUZZ_WEB_DIR

The relay owner is also listed as an admin using:

buzz-admin add-member --role admin

and

buzz-admin list-members

The relay continues to authenticate successfully.

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### Additional observations

The onboarding flow appears to be:

- Create Community → Builderlab only
- Join Community → Relay URL

There does not appear to be any equivalent relay-management UI for self-hosted deployments.

Builderlab-hosted communities expose Invite management.

Self-hosted communities do not.

I'm not sure if this is:

- intended behavior,
- a regression,
- or a missing feature for self-hosted relays.

Can someone clarify whether self-hosted relays are expected to expose Invite / Relay Access in Buzz Desktop?