fix: negate y-axis in graphics transform for correct symbol bounding boxes

Library symbols use y-up coordinates while schematics use y-down. The
_transform_local_point function was not negating y, causing asymmetric
symbols (e.g. power:VEE) to have their bounding boxes computed in the
wrong direction — missing overlaps with adjacent components.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

python/commands/schematic_analysis.py

@@ -332,8 +332,12 @@ def _transform_local_point(
 ) -> Tuple[float, float]:
     """
     Transform a point from local symbol coordinates to absolute schematic
-    coordinates using KiCad's transform order: mirror → rotate → translate.
+    coordinates using KiCad's transform order:
+    negate-y (lib y-up → schematic y-down) → mirror → rotate → translate.
     """
+    # Library symbols use y-up; schematic uses y-down
+    ly = -ly
+
     # Apply mirroring in local coords
     if mirror_x:
         ly = -ly