gemini retry support

[spinegar]

I seem to be hitting a quota with Gemini Flash 2.0. When this occurs, it would be great if the MCP server could implement a retry strategy using the retryDelay property in the error message.

Stagehand[browserbase_session_ad367ce1-ed23-4d00-8f70-3dce12e4de12_1762539928814_973009f6-15c1-4597-b6d4-0207019abe38]: Error during Google AI chat completion: {"error":{"code":429,"message":"You exceeded your current quota, please check your plan and billing details. For more information on this error, head to: https://ai.google.dev/gemini-api/docs/rate-limits. To monitor your current usage, head to: https://ai.dev/usage?tab=rate-limit. \n* Quota exceeded for metric: generativelanguage.googleapis.com/generate_content_paid_tier_input_token_count, limit: 4000000\nPlease retry in 47.434392449s.","status":"RESOURCE_EXHAUSTED","details":[{"@type":"type.googleapis.com/google.rpc.Help","links":[{"description":"Learn more about Gemini API quotas","url":"https://ai.google.dev/gemini-api/docs/rate-limits"}]},{"@type":"type.googleapis.com/google.rpc.QuotaFailure","violations":[{"quotaMetric":"generativelanguage.googleapis.com/generate_content_paid_tier_input_token_count","quotaId":"GenerateContentPaidTierInputTokensPerModelPerMinute","quotaDimensions":{"location":"global","model":"gemini-2.0-flash"},"quotaValue":"4000000"}]},{"@type":"type.googleapis.com/google.rpc.RetryInfo","retryDelay":"47s"}]}}