Add PostageTTL Option for All Beekeeper Checks

[gacevicljubisa]

Description

Each Beekeeper check should have a new option, PostageTTL, allowing users to define the time-to-live for a postage batch. This option should:

• Programmatically calculate the required block time.
• Retrieve the current postage price from the Bee node.
• Use the PostageTTL value to determine the appropriate amount for batch creation.
• The existing PostageAmount option should remain for backward compatibility. However, if PostageTTL is defined, it should take precedence, and PostageAmount should be recalculated accordingly.

This feature will simplify configuration settings and improve usability.

Tasks

• Add the PostageTTL option to all Beekeeper checks.
• Implement logic to calculate block time dynamically.
• Fetch the current postage price from the Bee node.
• Use PostageTTL to compute the required amount for batch creation.
• Ensure PostageAmount remains backward compatible but is recalculated if PostageTTL is set.