Hdpi 6864 defence pack

[arun-hmcts]

Jira link

https://tools.hmcts.net/jira/browse/HDPI-6864

Change description

Generates the defendant defence-form PDF and attaches it to the case so it's visible in Case File View and available for bulk-print distribution. Mirrors the claim-pack pipeline, reusing the shared formatter/mapper.

• On defendant response submission (citizen path only — legal-rep submissions are out of scope), schedules generation after the response transaction commits (db-scheduler
  CustomTask, retries + exponential backoff), keyed per defendant response.
• Builds the payload from the defendant's response: contact/identity, household circumstances, income & expenses, payment agreement, statement of truth, plus disputable
  fields — name, address, tenancy/notice details etc. resolved from the defendant's party_attribute_assertion (asserted value where present, else the claim baseline).
• England & Wales — Wales-only rows (landlord registered/licensed, household detail rows) gated by country.
• Income/expense row labels use the Cook design wording.
• Imports the rendered PDF into STATEMENTS_OF_CASE, types it DocumentType.DEFENDANT_RESPONSE, links it non-owning on DefendantResponseEntity.submissionDocument (lifecycle
  owned by PcsCaseEntity.documents; FK ON DELETE SET NULL), and logs the outcome to claim_activity_log against the defendant party. Idempotent — skips if a submission
  document already exists.

Testing done

Locally tested

Security Vulnerability Assessment

CVE Suppression: Are there any CVEs present in the codebase (either newly introduced or pre-existing) that are being intentionally suppressed or ignored by this commit?

• [x ] Yes
• No

Checklist

• commit messages are meaningful and follow good commit message guidelines
• README and other documentation has been updated / added (if needed)
• tests have been updated / new tests has been added (if needed)
• Does this PR introduce a breaking change