synthetic-unmapped-keys expectations (manually calculated, synthetic)
Each of two gemini messages has a token key beyond the six documented keys: surpriseKey or anotherUnknown. Preserve mapped fields and import the events. Record unmapped_usage_keys once per scan.
Expectations
- Two events. Summary: call_count=2, input_total_known=300, output_total_known=50, total_tokens_known=350, cache_read_known=None. Neither message reports cached; unknown is not replaced with zero.
- Exactly one unmapped_usage_keys diagnostic; the second extra-key message adds none.