feat(sequencer)!: Add new validator update action

[ethanoroshiba]

Summary

Added new action ValidatorUpdateV2, which houses the same functionality as ValidatorUpdate but now includes a name field.

Background

Previously, validator names were not stored app-side, and names could only be set in CometBFT genesis.

Changes

• Added ValidatorUpdateV2 action to protos and core.
• Added ValidatorNames struct, which contains address <> name key-value pairs.
• Added storage keys, value impls, snapshots, and state read/write methods for ValidatorNames.
• Added new ABCI query for validator name, accepting address as a parameter.

Testing

• Snapshot tests added for new VALIDATOR_NAMES storage key
• Unit tests for new state read/write methods
• Unit tests that new ABCI query works as expected
• Unit test for ABCI query router to validator_name_request.
• App execution test for ValidatorUpdateV2.
• Added ValidatorUpdateV2 to app_execute_transaction_with_every_action.

Breaking Changelist

• Non-consensus breaking, but added action to proto, triggering breaking changes notification from lint.

Related Issues

closes #1590