[Bug]: Connecting without a valid token to a token-required server shows empty homepage instead of failing

[tashda]

Summary

When connecting to a Z2M server that requires an auth token, providing no token (or an invalid token) still allows the connection to "succeed" — the app proceeds to the homepage but no content loads. The connection should fail explicitly so the user knows to provide a valid token.

Steps to reproduce

1. Point Shellbee at a Z2M bridge that has frontend.auth_token configured.
2. Leave the auth token field empty (or enter an invalid token).
3. Tap connect.

Expected

Connection fails with a clear error indicating an invalid/missing token. User stays on the connection screen.

Actual

Connection appears to succeed and the app navigates to the homepage, but device/group/state content never loads (the WS is presumably rejected or silently empty).

Notes

• Likely the WS handshake is treated as connected before the auth challenge is resolved, or auth failures aren't surfaced to the connection flow.
• Repro against the mock bridge by setting an auth token and connecting without one.