Introduce new method for implementing application synchronization loop

- Enable context to define loop stages, determining how many blocks can be processed in one turn.
- Adjust processing based on application distance to the head block.
- Add 'hive.app_next_iteration' procedure to automatically attach or detach context based on distance to the head block and predefined stages.
- 'hive.app_next_iteration' returns the range of block numbers to process dynamically.
- Applications can use the 'hive.get_stage' function to determine the current predefined stage of their context. Based on the stage, applications can perform actions such as enabling or disabling indices.
- 'hive.app_next_iteration' now issues a 'COMMIT' command. Applications using this new sync loop method should not issue 'COMMIT' within their synchronization loop.
- The previous method using 'hive.app_next_block' with explicit attach/detach calls remains valid and usable.
- Mixing the old method with the new 'hive.app_next_iteration' approach will cause undesired behavior and should be avoided.