refactor: convert ModelMetrics, RequestMetrics, TokenUsage to frozen dataclasses (#1066)#1068

microsasa wants to merge 3 commits intomainmicrosasa/cli-tools:mainfrom

issue-1066-frozen-dataclass-metrics-22f066193500edf7microsasa/cli-tools:issue-1066-frozen-dataclass-metrics-22f066193500edf7Copy head branch name to clipboard