docs(release-notes): tell customers with pre-zero-touch federation bundles to re-download

[cristim]

Summary

Customers who downloaded a federation IaC bundle before the zero-touch registration fix landed retain fail-quiet behaviour — their old copy silently skips registration unless manually edited. The fix (pre-filled contact_email from Session.Email, unconditional registration) only takes effect in bundles downloaded after the fix ships. There's no way to back-fix already-downloaded files.

Captured in: known_issues/27_federation_old_bundle_redownload_notice.md

Current behaviour

Old bundles include:

• Terraform registration.tf with do_register = var.cudly_api_url != "" && var.contact_email != ""
• CLI shell scripts gated on if [[ -n "${CUDLY_CONTACT_EMAIL:-}" ]]; then ...
• CFN deploy scripts with no registration curl call at all

Customers who downloaded these before the zero-touch fix landed complete their deploy without auto-registration. They never see an error — registration just silently doesn't happen.

Expected behaviour

The next release notes / CHANGELOG entry should tell affected customers to re-download the bundle:

If you downloaded a federation IaC bundle before [release date], re-download it from the CUDly UI to get zero-touch registration (the bundle now auto-registers your account with no manual edits required).

Steps to reproduce

1. Download a federation bundle before fix(iac): drop email gate from Terraform registration.tf across all bundles.
2. Run the bundle. terraform apply succeeds.
3. Observe: CUDly account not registered; no error surfaced anywhere.

Proposed fix

One-line addition to the next release notes / CHANGELOG entry. No code change.

References

• Companion commits:
  • fix(iac): drop email gate from Terraform registration.tf across all bundles
  • fix(iac): always run registration in CLI shell scripts; tighten error handling
• Known-issue doc: known_issues/27_federation_old_bundle_redownload_notice.md.

Severity

Low — silently missing post-install step; customers notice only when they expect their account to appear in CUDly and don't see it.

Effort

Trivial — ~3 lines of release-notes prose. Action required when the next release is drafted.

[cristim]

Verification (PR #64 → sha dab3618, deployed via rollup in 2026-04-25T13:21:29Z AWS Lambda run)

This is a docs-only change to CHANGELOG.md — it's not surfaced in the runtime UI, so verification is "the notice text is on the deployed branch and shipped in the artifact":

$ git show origin/feat/multicloud-web-frontend:CHANGELOG.md | sed -n '7,17p'
### Notices

- **Federation IaC bundles downloaded before 2026-04-22 need to be
  re-downloaded** to get zero-touch registration. Older bundles silently
  skip auto-registration unless manually edited (Terraform `registration.tf`
  gated `do_register` on `cudly_api_url`; CLI shell scripts included the
  registration call only when `CUDlyAPIURL` was present at render time;
  CloudFormation deploy scripts had no registration call at all).
  Re-download the bundle from the CUDly UI and the new copy will register
  your account automatically with no manual edits required.

The notice appears under ## [Unreleased] / ### Notices — the right place to land for the next tagged release. The three bundle-render code paths covered (Terraform registration.tf, CLI shell scripts, CloudFormation) match the exact set the issue called out as needing re-download.

Runtime curl verification isn't applicable here (no UI surface, no API endpoint serving the changelog). Closing on docs-merged proof.