[V133-specific] Add upgrade proposal functionality

Add upgrade proposal functionality with message handling for proposing, approving, and rejecting upgrades. Introduce upgrade management in the app and keeper layers, including new protobuf definitions for upgrade messages.

Summary by CodeRabbit

Release Notes

• New Features

  • Added upgrade proposal, approval, and rejection workflow via new CLI commands (propose-upgrade, approve-upgrade, reject-upgrade).
  • Implemented majority-vote-based upgrade scheduling and execution.
  • Added query endpoints for upgrade proposals and status.
  • Enabled multi-validator cluster support.
  • Added ARM64 Docker support for Apple Silicon.

• Improvements

  • Enhanced validator churn management with improved timing and validation.
  • Upgraded TimescaleDB image for better performance.

• Version

  • Released as version 2.0.0.