ProtocolPausingPolicy

• Purpose: Allow protocol-level operators to pause actions across all nodes simultaneously.

• Guarded selectors: Same set as NodePausingPolicy.

• Config: Registry owner whitelists protocol pausers via add(users) / remove(users). Whitelisted accounts can pause/unpause selectors or trigger a global pause with the corresponding functions (no per-node scoping).

• Behavior: Reverts with GlobalPause() when globally paused or SigPause(selector) when that selector is paused.