Mitsubishi integration stuck in partial error state if Mitsubishi account contains units in multiple sites

### The problem

The Home Assistant integration for Mitsubishi heat pumps will be stuck in an error status if you have multiple locations in the same Mitsubishi account.

For example, home 1 has 4 heat pumps, these are recognized correctly from my home Home Assistant, however vacation rental home 2 which is registered to the same Mitsubishi Comfort account has 2 heat pumps and these are also picked up by the Home Assistant integration at home 1, but in error status because the IPs were unknown. Disabling the two remote heat pump entities from home 1's HA does not make the integration error go away for the two devices it cannot find on the local network.

Mitsubishi Comfort (Kumo) supports multiple locations per account but it doesnt appear the integration was written to support that. It would be idea if the integration would be set to ignore disabled entities when trying to obtain an IP or if you could select which units to include in the integration and have the integration not in error status if units in other geographic sites arent found on the same local network as the HA installation.

The issue only occurs with the units that are not local to the same Mitsu Comfort location as the HA, all local units are working correctly.

### What version of Home Assistant Core has the issue?

core-2026.9.0

### What was the last working version of Home Assistant Core?

_No response_

### What type of installation are you running?

Home Assistant OS

### Integration causing the issue

mitsubishi_comfort

### Link to integration documentation on our website

_No response_

### Diagnostics information

_No response_

### Example YAML snippet

```yaml

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### Anything in the logs that might be useful for us?

```txt

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### Additional information

Start by inspecting the `mitsubishi_comfort` integration and reproduce the account setup with units at multiple sites. Trace how discovered units are mapped to local IPs and how disabled or unreachable remote units affect the integration status. Done means local units continue working and remote-site units no longer leave the integration in an error state, with tests covering the behavior.

Written by the indexing model from the issue text.