* feat(vision-bridge): add automatic image description fallback for non-vision models
Implements VisionBridgeGuardrail (priority 5) that intercepts image-bearing
requests to non-vision models, extracts descriptions via a configurable
vision model (default: gpt-4o-mini), and replaces images with text before
forwarding. Fails open on any error.
- Add VisionBridgeGuardrail class extending BaseGuardrail
- Add visionBridgeHelpers: extractImageParts, callVisionModel, replaceImageParts, resolveImageAsDataUri
- Add visionBridgeDefaults with configurable settings
- Register VisionBridgeGuardrail in GuardrailRegistry at priority 5
- Add 51 unit tests covering all spec scenarios (VB-S01 through VB-S10)
- Dependency injection for getSettings and callVisionModel (testable without SQLite)
Closesdiegosouzapw/OmniRoute#1424
* fix(vision-bridge): resolve Anthropic API, parallel processing, provider keys, structuredClone