[anisaoshafi]

cdklocal now prints a deprecation notice to stderr on every run. It points users to lstk cdk and the migration guide. It reuses the notice structure from the localstack CLI (DEVX-1126).

============================================================================
  WARNING: 'cdklocal' is deprecated. Use 'lstk cdk' instead.
============================================================================

  'cdklocal' no longer receives updates.

  Get started with 'lstk', the new LocalStack CLI:
  https://docs.localstack.cloud/aws/developer-tools/running-localstack/lstk/

  Switch your scripts and CI workflows to 'lstk cdk':
  https://docs.localstack.cloud/aws/developer-tools/running-localstack/lstk/migration/#infrastructure-as-code

============================================================================

Continuing with 'cdklocal'...

• Stdout stays clean, so piped output still works.
• DISABLE_DEPRECATION_NOTICE=1 hides the notice.
• Adds the same note to the README and bumps the version to 3.1.0.
• CI fix: pins aws-cdk-lib to the template minimum for pinned CLI versions. The latest library needs CDK CLI 2.1144.0+, so the 2.1113.0 job failed on main too.

Resolves DEVX-1169