feat: Add PlacementOptions support to Rokt integration

[thomson-t]

Background

The Rokt integration start time is not captured when the partner invokes selectPlacements.
Add PlacementOptions and add support for integrationStartTimestamp to pass it down to the Rokt Kit.

What Has Changed

• Add integration start timestamp to the PlacementOptions object and pass it down to RoktKit
• Add unit tests

Screenshots/Video

N/A

Checklist

• I have performed a self-review of my own code.
• I have made corresponding changes to the documentation.
• I have added tests that prove my fix is effective or that my feature works.
• I have tested this locally.

Additional Notes

• {Any additional information or context relevant to this PR}

Reference Issue (For employees only. Ignore if you are an outside contributor)

• Closes https://go/j/SDKE-728

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud