fix: add pause guard coverage to insurance mutators

[AbuJulaybeeb]

What was done

• Added PauseAdmin and Paused state management keys to the insurance contract.
• Implemented global and function-level pause constraints matching other contract architectures (savings_goals, bill_payments).
• Integrated require_not_paused() guards into create_policy, pay_premium, deactivate_policy and related administrative functions.
• Resolved compilation issues in insurance/src/test.rs caused by unclosed delimiters and macro corruption.
• Re-added unintentionally dropped instance TTL constants back to remitwise-common.

Why it was done

To fulfill #714, the insurance contract previously lacked an emergency killswitch mechanism. This modification ensures that any sudden anomalies can be halted globally or per-function by an administrator without risking user funds or corrupted coverage.

How it was verified

• Verified logic manually by running cargo test -p insurance utilizing newly written coverage for global- and function-level pause guards over mutator actions.

closes #714

[Baskarayelu]

pause-guard coverage on the insurance mutators - exactly the circuit-breaker behaviour we wanted verified. merging 👍