Severity Curation Enhancements

1. Highlight PURL in bold.

Replace:

> Conflicting CVSS 3.1 Scores
> Conflicting severity scores for package: `pkg:pypi/deepspeed`

With:

> Conflicting CVSS 3.1 for: pkg:pypi/deepspeed

2. Show affected and fixed version ranges for PURL.

3. Add tooltip for each CVSS metric.

4. Collapse Temporal and Environmental score sections by default if none of the advisories include those metrics.

5. Remove "hide/show" button for CVSS vector string.