Fix TikTok stream worker TypeScript typing errors

[cvsz]

Motivation

• Resolve TypeScript errors caused by redis.xadd returning string | null and redis.xreadgroup returning unknown that prevented a clean build and could crash the worker loop.
• Harden the TikTok stream worker so malformed Redis responses are skipped and do not stop the worker.

Description

• Ensure enqueueTikTokWebhookEvent awaits redis.xadd into streamId, checks for a falsy result and throws Error if the stream ID is missing so the function always fulfills Promise<string>.
• Add RedisStreamEntry and RedisStreamGroupResponse aliases and implement isRedisStreamGroupResponse runtime type guard to narrow the xreadgroup response safely.
• Log and skip unexpected/malformed xreadgroup responses instead of iterating them, preventing runtime iteration errors.
• Small refactor to iterate only validated stream entries before calling processStreamEntry.

Testing

• Ran npm run build in app/ to validate TypeScript compilation and confirm the original TS2322 (string | null assignment) and TS2488 (unknown iteration) errors are resolved.
• The npm run build command still fails in this environment due to unrelated missing dependencies/type declarations across the repository (external @types/node and other packages), so full project compilation is blocked but the targeted TikTok stream issues are fixed.

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Codex Task

[chatgpt-codex-connector]

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[gemini-code-assist]

Code Review

This pull request updates the TikTok webhook enqueuing process to return the stream ID and introduces a type guard, isRedisStreamGroupResponse, to validate the structure of Redis stream responses before processing. A security concern was identified regarding the logging of the entire response object when validation fails, as it could lead to the exposure of sensitive information.