Migrate llm-judge image to TrustyAI registry and add image build automation

### Problem

Currently using personal registry for llm-judge detector images:

```yaml
image: quay.io/spandraj/guardrails-detector-judge:latest
```

### Solution
1. Migrate to official TrustyAI registry: `quay.io/trustyai/guardrails-detector-judge:latest`
2. Add automated image build pipeline
