Screenshots from a new run are added to the same build when scenarioName is provided

Description

When scenarioName is set to the same value as the screenshot/image name and platform + env are not provided, VRT reuses the existing build on a subsequent run instead of creating a new one. As a result, screenshots from the new run are appended to the previous build rather than being tracked as a separate run.

Steps to Reproduce

1. Create a test run with:
   • ciBuildId set to some build identifier
   • scenarioName set to the same value as the screenshot/image name
   • platform and env left unset / not provided
2. Submit screenshots — build is created and screenshots are associated correctly.
3. Trigger a new run (new CI execution) with the same configuration.
4. Observe that the new screenshots are added into the existing build instead of a new one being created.

Expected Behavior

A new run should always create a new build entry. The build resolution logic should not reuse an existing build when a fresh run is initiated, regardless of whether scenarioName matches the screenshot name and platform/env are absent.

Actual Behavior

When scenarioName equals the screenshot name and platform/env are omitted, VRT finds the existing build by matching on scenarioName alone and appends new run screenshots to it instead of creating a new build.

Root Cause (suspected)

The build lookup query likely matches on scenarioName without also requiring a unique run identifier, causing it to collide when platform and env are null/empty and the scenarioName mirrors the image name.

Impact

• Build history is polluted with screenshots from multiple runs merged into one build.
• Difficult to distinguish which screenshots belong to which CI execution.

Environment

• Self-hosted on GCP VM via Docker Compose
• VRT backend: 5.1.2

No source file or test is named. Start by tracing the backend build-resolution path for submissions using ciBuildId, scenarioName, platform, and env, then reproduce the two-run case described here. Done means separate runs create separate build entries and the relevant regression coverage passes.