fix: TaskTracer validation error (Fixes #55)

[zmyzxb]

Describe this PR

This PR fixes a validation error that occurred when passing a numeric task_id to the trace command. Previously, Fire parsed --task_id=15 as an integer, which was then propagated to TaskTracer as both task_id and task_name, causing Pydantic to raise a string type validation error. The fix is to cast task_id to a string when calling single_task explicitly.

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[Copilot]

Pull Request Overview

This PR fixes a validation error in the task tracing functionality when numeric task IDs are passed via command line arguments. The issue occurred because Fire parsed --task_id=15 as an integer, but the single_task function expects a string parameter.

• Cast numeric task_id to string when calling single_task function

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