DDS: BlueCat Edge: Add site IDs textbox support

[shubhamvekariya-crest]

What does this PR do?

• Update README steps to include how to get Site IDs from BlueCat Edge.
• Here is the Slack discussion link for reference: https://crestdatasystems.slack.com/archives/C067GU53VEW/p1775217965866609?thread_ts=1770125063.151259&cid=C067GU53VEW

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Add the qa/skip-qa label if the PR doesn't need to be tested during QA.
• If you need to backport this PR to another branch, you can add the backport/<branch-name> label to the PR and it will automatically open a backport PR once this one is merged

[github-actions]

⚠️ Recommendation: Add qa/skip-qa label

This PR does not modify any files shipped with the agent.

To help streamline the release process, please consider adding the qa/skip-qa label if these changes do not require QA testing.