Add --verbose/-v flag to gt costs command that outputs debug information
when silent failures occur during cost tracking operations:
- wisp list failures in querySessionCostWisps and deleteSessionCostWisps
- bd show failures when querying wisp details
- JSON unmarshal failures when parsing wisp/event data
- payload unmarshal failures when parsing session payloads
This makes debugging cost tracking issues much easier as these error
paths previously continued silently without any indication of failure.
Closes: bd-qv8f9
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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