fix: Flip() after board.Add() to avoid 30s hang in KiCAD 9

FootprintLoad+Flip() on standalone footprint (not yet in board) causes
a 30-second block in KiCAD 9 pcbnew. Solution: add footprint to board
first, then call Flip() with board context available.

Fixes B.Cu placement timeout that killed the Python process.

python/commands/component.py

@@ -125,19 +125,20 @@ class ComponentCommands:
             angle = pcbnew.EDA_ANGLE(rotation, pcbnew.DEGREES_T)
             module.SetOrientation(angle)
 
-            # Set layer — for B.Cu the footprint must be flipped (mirrored),
-            # not just layer-assigned.  Flip() handles layer + mirror in one step.
-            if layer == "B.Cu":
-                if not module.IsFlipped():
-                    module.Flip(module.GetPosition(), False)
-            else:
+            # Set layer for F.Cu (or non-B.Cu) before adding to board
+            if layer != "B.Cu":
                 layer_id = self.board.GetLayerID(layer)
                 if layer_id >= 0:
                     module.SetLayer(layer_id)
 
-            # Add to board
+            # Add to board first — Flip() requires board context in KiCAD 9
             self.board.Add(module)
 
+            # Flip to B.Cu after add (board context needed, otherwise hangs 30s)
+            if layer == "B.Cu":
+                if not module.IsFlipped():
+                    module.Flip(module.GetPosition(), False)
+
             return {
                 "success": True,
                 "message": f"Placed component: {component_id}",