CodeQL zero to hero part 5: Debugging queries

This post teaches how to debug and improve CodeQL taint-tracking queries by walking through a Gradio-based unsafe deserialization example (user-uploaded file passed via `gr.File.name` to `open()` and `pickle.load`). It shows how to minimize examples, use Quick Evaluation, AST viewer, and `getAQlClass`, analyze partial path graphs to find where taint stops, and add targeted taint steps (e.g., attribute read of `name`, propagation through `open`) to reach deserialization sinks, culminating in a refined, more maintainable query.