feat: add release automation for v2 packages

[just-mitch]

Add release-please v2 configuration and release branch automation

This PR introduces a new release management system for Aztec Packages v2:

1. Adds .github/release-please-v2.json configuration file with:

   • Simple release type settings
   • Custom changelog sections
   • PR title patterns and headers

2. Creates a new workflow for release branch management:

   • Adds .github/workflows/create-release-branch.yml to automate creating version branches
   • Workflow extracts current version from manifest and creates appropriate branch
   • Automatically increments major version in manifest after branch creation

3. Enhances the existing release-please workflow:

   • Adds support for version branches (v[0-9]+)
   • Implements automatic RC tag generation with incremental numbering
   • Prevents duplicate tagging of commits

4. Updates CI workflow to properly handle RC releases:

   • Modifies condition in ci3.yml to recognize -rc. tags in addition to -nightly. tags

5. Removes the obsolete .github/actions/setup-k8s-terraform/action.yml file

[just-mitch]

• feat: add release automation for v2 packages #16681 👈 (View in Graphite)
• feat: spartan/bootstrap.sh network_deploy #16639 : 1 other dependent PR (#16648 )
• feat: create test-network-scenarios.yml #16595
• feat: create deploy-aztec-infra.yml #16580
• feat: scaffold deploy-scenario-network.yml #16553
• feat: create deploy-rollup-contracts.yml #16549
• feat: deploy-eth-devnet.yml github action #16538
• next

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