Review-feedback follow-up. Pre-fix, A2A_IDLE_TIMEOUT_SECONDS=foo or =-30
fell back to the default with zero log signal — operator sets the wrong
value, sees "no effect," wastes hours debugging "why is my override not
working." Now bad-input cases log a clear message naming the variable,
the bad value, and the default applied.
Refactor: extract parseIdleTimeoutEnv(string) → time.Duration so the
parse logic is unit-testable. defaultIdleTimeoutDuration is a const so
tests reference it without re-deriving the value.
8 new unit tests cover empty / valid / negative / zero / non-numeric /
float / trailing-units inputs.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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