analyze: drop stale ty:ignore on plotstyle import

plotstyle is now a real installed package (from the git.larsbogner.de
index) with its own type info, so the unresolved-import suppression
is no longer needed.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

giant/analysis/render.py

@@ -17,7 +17,7 @@ import subprocess
 from pathlib import Path
 
 import numpy as np
-import plotstyle as ps  # ty: ignore[unresolved-import]
+import plotstyle as ps
 import yaml
 
 from giant.analysis.reduced import Reduced