fix: remove unnecessary f-string prefixes and unused import (#2352)

- Remove f-string prefix on 7 strings with no placeholders (F541)
  in analyze.py, aggregate_benchmark.py, run_loop.py, generate_review.py
- Remove unused `os` import in quick_validate.py (F401)

Found by ruff via HUMMBL Arbiter (https://hummbl.io/audit).

skills/public/skill-creator/eval-viewer/generate_review.py

@@ -447,8 +447,8 @@ def main() -> None:
         port = server.server_address[1]
 
     url = f"http://localhost:{port}"
-    print(f"\n  Eval Viewer")
-    print(f"  ─────────────────────────────────")
+    print("\n  Eval Viewer")
+    print("  ─────────────────────────────────")
     print(f"  URL:       {url}")
     print(f"  Workspace: {workspace}")
     print(f"  Feedback:  {feedback_path}")
@@ -456,7 +456,7 @@ def main() -> None:
         print(f"  Previous:  {args.previous_workspace} ({len(previous)} runs)")
     if benchmark_path:
         print(f"  Benchmark: {benchmark_path}")
-    print(f"\n  Press Ctrl+C to stop.\n")
+    print("\n  Press Ctrl+C to stop.\n")
 
     webbrowser.open(url)
 

skills/public/skill-creator/scripts/aggregate_benchmark.py

@@ -389,7 +389,7 @@ def main():
     configs = [k for k in run_summary if k != "delta"]
     delta = run_summary.get("delta", {})
 
-    print(f"\nSummary:")
+    print("\nSummary:")
     for config in configs:
         pr = run_summary[config]["pass_rate"]["mean"]
         label = config.replace("_", " ").title()

skills/public/skill-creator/scripts/quick_validate.py

@@ -4,7 +4,6 @@ Quick validation script for skills - minimal version
 """
 
 import sys
-import os
 import re
 import yaml
 from pathlib import Path

skills/public/skill-creator/scripts/run_loop.py

@@ -188,7 +188,7 @@ def run_loop(
 
         # Improve the description based on train results
         if verbose:
-            print(f"\nImproving description...", file=sys.stderr)
+            print("\nImproving description...", file=sys.stderr)
 
         t0 = time.time()
         # Strip test scores from history so improvement model can't see them