Summary

Recent refactors in Opportunity validation introduced custom exceptions
to separate business logic from trigger/UI handling.

However, current test coverage is limited and does not fully assert
negative scenarios or exception behavior.

Suggested Solution

Add unit tests for Opportunity validation to cover:

• Invalid stage + probability combinations
• Missing required fields
• Proper custom exception handling

Ensure that all existing tests continue to pass and no production
logic is modified.

Alternative Solutions

None considered. The best approach is to add targeted test cases
without modifying existing validation logic.

Code of Conduct

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