add order history cleanup utility

[kirito201922]

Adds a script that prunes closed orders from a local order history JSON, reducing file size and improving performance.

---

Note

Introduces a Python utility to prune closed orders from data/order_history.json to keep history size manageable.

• Adds scripts/python/clean_order_history.py that filters out orders with status == "closed" and rewrites the JSON (pretty-printed)
• Handles missing history file gracefully and prints a summary of removed vs remaining orders

^{Written by Cursor Bugbot for commit 5d9270f. This will update automatically on new commits. Configure here.}

[cursor]

Script adds "orders" key to files lacking it

The code unconditionally assigns data["orders"] even when the original JSON file doesn't contain an "orders" key. If run on a file without this key, the script will add "orders": [] to the file structure rather than leaving it unchanged. A cleanup utility probably shouldn't modify files that have no matching data to clean. The logic uses data.get("orders", []) to safely read, but then always writes back via assignment.