[Bug]: Investigate DNS search path / resolver priority improvements.

### I have done the following

- [x] I have searched the existing issues
- [x] If possible, I've reproduced the issue using the 'main' branch of this project

### Steps to reproduce

As pointed out by @austinlparker, there's a Tailscale issue that's open that identifies some possible ways for `container` to play more nicely when resolving plain hostnames.

The post in the issue containing the analysis is: https://github.com/tailscale/tailscale/issues/17096#issuecomment-3416342435

### Current behavior

Tailscale short hostnames (e.g., stan, kenny) to fail resolution, even though Tailscale MagicDNS is properly configured and full domain names work correctly.

### Expected behavior

MagicDNS should function properly.

### Environment

```markdown
- OS: macOS 26.1
- Xcode: Xcode 26
- Container: 0.6.0
```

### Relevant log output

```shell
N/A
```

### Code of Conduct

- [x] I agree to follow this project's Code of Conduct