Stabilize Cardano DB v2 client CLI/library - Phase 3

[jpraynaud]

Why

We want to make the Cardano DB v2 certification stable and provide seamless forward/backward compatibility for users.

What

Use the v2 backend as default in the cardano-db command.

How

• Update the dev blog post:
  • Split the phase "Distribution +2" (one phase for v2 backend as default and another for deprecation of v1) (@jpraynaud)
  • Plan for update of the blog post with next distribution (@jpraynaud)
• Make the v2 backend as default in the client CLI
• Tests:
  • Aggregator stress test if necessary
  • Check all manual CI workflows
    • Mithril Client multi-platform test
  • E2e test
• Update documentation:
  • Mithril client node commands
  • Upgrade the guide for bootstrapping a Cardano node with restoration of a range of immutable