feat: migrate rules/commands to .cursor and add .dev scripts

Author: wislertt

.cursor/.dev/problem_lists/utils.py

@@ -1,24 +1,9 @@
 """Shared utilities for problem list management."""
 
-import json
-from pathlib import Path
+from leetcode_py.cli.utils.problem_finder import _build_problem_number_cache
 
 
 def get_existing_problems():
     """Get problem numbers from existing JSON files."""
-    # Get the project root (3 levels up from this file)
-    project_root = Path(__file__).parent.parent.parent
-    json_dir = project_root / "leetcode_py/cli/resources/leetcode/json/problems"
-    existing_problems = set()
-
-    for json_file in json_dir.glob("*.json"):
-        try:
-            with open(json_file, "r") as f:
-                data = json.load(f)
-                problem_number = int(data.get("problem_number", 0))
-                if problem_number > 0:
-                    existing_problems.add(problem_number)
-        except (json.JSONDecodeError, ValueError, KeyError):
-            continue
-
-    return existing_problems
+    cache = _build_problem_number_cache()
+    return set(cache.keys())

.cursor/commands/problem-creation.md

@@ -19,6 +19,14 @@ When user requests a problem by **number** or **name/slug**, the assistant will:
 8. **Verify** with `make p-lint` - fix template issues in JSON if possible, or manually fix generated files if template limitations
 9. **Iterate** if JSON fixes: re-run `make p-gen PROBLEM={problem_name} FORCE=1` and `make p-lint` until passes to ensure reproducibility
 
+**If user does not specify a problem number or name/slug**, run:
+
+```bash
+poetry run python .cursor/.dev/next_problem.py
+```
+
+This will suggest the next problem to work on from the available problem lists based on completion status.
+
 ## Scraping Commands
 
 ```bash