shell: deprecate applied argument and introduce validated one in mempool RPCs

Context

This MR deprecate the applied argument and introduce validated in the pending_operations and monitor_operations RPCs.

This MR also rename the applied field in pending_operations result into validated for version 2 of this RPC.

It also updates some test helper to use by default the version 2 of pending_operations RPC.

This MR fixes #5720 (closed)

Manually testing the MR

CI green

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
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