per Claude:

Three fixes across two files:

• config_flow.py — CONNECTION_CLASS removed. config_entries.CONN_CLASS_CLOUD_POLL was deprecated and then removed in a recent HA version. Since the config flow class is instantiated during the setup attempt, hitting this AttributeError at class definition time would cause the entire module to fail silently — which matches "no logs" exactly. This is almost certainly the primary cause of your "internal" error.
• config_flow.py — error logging fixed. Both exception handlers now log at ERROR level with exc_info=True (which includes the full traceback). Previously they only logged at DEBUG, meaning you'd never see them unless you specifically enabled debug logging. With this fix, the next time something goes wrong you'll see exactly what it is in the HA logs.
• models.py — invalid union type fixed. Optional[int] | Optional[str] is not valid Python type syntax — it's redundant and dacite can't handle it. Changed to Optional[int | str] which is the correct form. This would cause a WrongTypeError from dacite whenever the API returns a non-integer status value, which would also produce "internal".
  Deploy config_flow.py first — that's the most likely cause. With the improved logging in place, if there's still an issue after that you'll see exactly what it is.

I'm able to connect with HA 2026.1 after applying this change.