Stabilize Cardano DB v2 client CLI/library - Phase 2

[jpraynaud]

Why

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

What

Stabilize the v2 backend in the cardano-db command and prepare for v1 backend deprecation.

How

• Mithril client CLI:
  • Decommission cardano-db-v2 command
  • Add the cardano-db-v2 command in the list of removed commands if needed
  • Make the v2 backend stable in cardano-db command
  • Update the end to end test to not use --unstable option for the v2 backend
  • Use db folder by default in v2 backend instead of db_v2
    • in client CLI
    • in github actions test-client.yml
  • Update the dev blog post on the imminent switch to v2 backend by default (to be planned with the next distribution) (@jpraynaud)
• Mithril aggregator:
  • Make only MithrilStakeDistribution non optional signed entity type:
    • Keep only MithrilStakeDistribution in the hard coded values (DEFAULT_ALLOWED_DISCRIMINANTS)
    • Modify the example of the signed_entity_types configuration of the aggregator
    • Update the e2e test to use CardanoStakeDistribution and CardanoImmutableFilesFull (signed_entity_types in main configuration)
    • Check if the aggregator stress test needs to be modified
    • Update the list of signed entity types in the GitHub actions manual workflows if needed and run the workflows with success:
      • Aggregator stress test
      • Backward compatibility
      • Mithril Client multi-platform test
    • Add CardanoImmutableFilesFull in GitHub environment variables:
      • dev-preview (@jpraynaud)
      • dev-follower-preview (@jpraynaud)
      • dev-mainnet (@jpraynaud)
      • testing-preview (@jpraynaud)
      • pre-release-preview (to be planned with the next distribution)
      • release-preprod (to be planned with the next distribution)
      • release-mainnet (to be planned with the next distribution)
• Update documentation:
  • Mithril client node commands
  • Upgrade the guide for bootstrapping a Cardano node with restoration of a range of immutable