Developer Fixes Test Suite Gap After Reader Flags Boundary-Testing Blind Spot

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A developer building an Electricity Planning Engine received a comment from reader Alex Shev pointing out that energy workflow tests should cover boundary conditions, not just midpoint values. Upon reviewing the existing test suite, the developer found that every peak and off-peak assertion used timestamps comfortably inside their respective windows, none near the actual transition points. The gap mattered because a wraparound time comparison in TimeSlot::contains() could silently return a wrong price at boundary moments without throwing any error. To address this, the developer added four targeted assertions covering the minute before a window opens, the exact opening second, the minute before it closes, and the exact closing second. The fix was validated by intentionally breaking the comparison logic, confirming the new boundary tests failed at precisely the expected points.

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