cmdx v2 is a major rewrite of the Ruby framework for building maintainable business processes. The v1 state-machine and Zeitwerk architecture is replaced by a signal-based runtime, immutable frozen Results, fiber-local chains, and a slimmer registry surface. Key additions include a new CMDx::Runtime orchestrating the full task lifecycle, CMDx::Telemetry pub/sub for lifecycle events, CMDx::Input/Output replacing the old Attribute system, saga-style pipeline rollback, parallel task execution with configurable executors and mergers, correlation IDs, i18n support via I18nProxy, and multiple new retry jitter strategies. Several breaking changes require renaming `def call` to `def work`, updating result access patterns, and migrating from removed classes like Parallelizer, Attribute, and various Utils modules.
