Add the pauser role to some contracts

[evercoinx]

Note

High Risk
Changes who can pause()/unpause() on six upgradeable mainnet contracts; if PAUSER_ROLE is not granted during upgrade/deploy, contracts can become unpausable during incidents. Also updates deployment/upgrade automation paths, which are operationally sensitive.

Overview
Separates pausing from admin governance by introducing PAUSER_ROLE on PolicyManager, ClaimManager, PremiumManager, SpecRegistry, Swapper, and CoverPoolFactory, and switching pause()/unpause() to require onlyRole(PAUSER_ROLE) instead of DEFAULT_ADMIN_ROLE.

Updates deployment and interfaces to support a dedicated pauser: adds PAUSER env var, wires PAUSER_ROLE grants during Deploy.s.sol role configuration, and extends interfaces/mocks/tests accordingly. Adds mainnet-focused upgrade tooling and documentation, including Ethereum-specific upgrade scripts (notably a ClaimManager variant that skips initializeV2) and a runbook describing batching upgrades with grantRole to avoid a no-pauser window.

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[dB2510]

Can you please confirm if all the new pauser role variables in the all the contracts are compatible with already deployed contracts?

[evercoinx]

Can you please confirm if all the new pauser role variables in the all the contracts are compatible with already deployed contracts?

The current changes are totally upgrade safe.