Add vault pause transition tests

[Brainoncrack]

Description

Difficulty: Expert

Type: Test

Summary

Add tests for entering and exiting pause state if pause support exists.

Current Behaviour

Pause transitions can create unsafe or confusing contract behaviour.

Expected Behaviour

The contract should only allow authorised pause changes and should preserve accounting state.

Suggested Implementation

Test authorised pause, unauthorised pause, unpause, and user operation behaviour during pause.

Files or Areas Likely Affected

tests/
src/

Acceptance Criteria

• Authorised pause is tested.
• Unauthorised pause is rejected.
• Unpause is tested.
• Accounting state remains unchanged.
• Paused operation behaviour is verified.

Additional Notes

Only implement if pause is part of the design.

[Adebisi1111]

I intend to work on this issue.

[Adebisi1111]

I intend to work on this issue on behalf of @Adebisi1111 — please assign it to us under the Official Campaign | FWC26.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign | FWC26 campaign!

@Adebisi1111's PR #398 was approved and merged by @El-swaggerito.

🏆 @Adebisi1111: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (258 total points). Track your full progress on GrantFox.

👏 Great work, @Adebisi1111! Keep contributing to Axionvera.