UID2-7937 Create one release per Docker workflow

[swibi-ttd]

Summary

• disable GitHub release creation in each of the 14 image publisher jobs
• create one workflow-level release after every image publishes successfully
• skip release creation for Snapshot runs
• include all 14 version-pinned GHCR images in the release notes

Root cause

Each shared Docker publish job attempted to create the same version release concurrently, causing already_exists failures after the images had been published.

Validation

• actionlint .github/workflows/release-all-docker-images.yaml
• git diff --check
• structural checks for 14 publishers, dependencies, and image references

Jira

• https://thetradedesk.atlassian.net/browse/UID2-7937

Evidence

• https://github.com/IABTechLab/uid2-examples/actions/runs/35673190467

[Copilot]

Copilot was unable to review this pull request because the user who requested the review has reached their quota limit.