⚡ Bolt: [performance improvement] Prevent list materialization in variable_level AST traversal

[tachyon-beep]

💡 What: Changed _assignment_callee and _collect_return_paths in src/wardline/scanner/taint/variable_level.py to accept Iterable[ast.AST] and passed ast.iter_child_nodes() directly instead of materializing them into lists.
🎯 Why: Eagerly materializing AST nodes into lists during deep recursive AST traversal creates unnecessary memory allocations and GC pressure.
📊 Impact: Reduces memory allocations during Level 2 taint analysis (which is a hot path).
🔬 Measurement: Observe lower memory usage and slightly faster execution times during large AST analysis workloads.

---

PR created automatically by Jules for task 6756327243091457610 started by @tachyon-beep

[google-labs-jules]

👋 Jules, reporting for duty! I'm here to lend a hand with this pull request.

When you start a review, I'll add a 👀 emoji to each comment to let you know I've read it. I'll focus on feedback directed at me and will do my best to stay out of conversations between you and other bots or reviewers to keep the noise down.

I'll push a commit with your requested changes shortly after. Please note there might be a delay between these steps, but rest assured I'm on the job!

For more direct control, you can switch me to Reactive Mode. When this mode is on, I will only act on comments where you specifically mention me with @jules. You can find this option in the Pull Request section of your global Jules UI settings. You can always switch back!

New to Jules? Learn more at jules.google/docs.

---

For security, I will only act on instructions from the user who triggered this task.

[chatgpt-codex-connector]

You have reached your Codex usage limits for code reviews. You can see your limits in the Codex usage dashboard.

[Copilot]

Pull request overview

This PR optimizes Level 2 taint analysis AST traversal by avoiding eager list(...) materialization during deep recursive walks, reducing allocation and GC overhead in a hot path.

Changes:

• Updated _assignment_callee and _collect_return_paths to accept Iterable[ast.AST] rather than list[ast.AST].
• Passed func_node.body and ast.iter_child_nodes(...) directly to traversal helpers instead of wrapping them in list(...).
• Added a Jules “bolt” note documenting the performance guideline for future AST traversals.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/wardline/scanner/taint/variable_level.py	Removes eager list materialization in recursive AST traversals by switching helper signatures to Iterable and passing iterators directly.
.jules/bolt.md	Documents the optimization rationale and a guideline to avoid list(ast.iter_child_nodes(...)) in hot-path traversals.

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.