Fix SolverCalculiX object refactor (#20913)

Rename original SolverCalculix.ui to SolverCcxTools.ui to prevent
collision on case insensitive filesystems.

Fixes: 4f7a835e22 ("Fem: SolverCalculiX object refactor")

src/Mod/Fem/Gui/CMakeLists.txt

@@ -428,8 +428,8 @@ SET(FemGuiPythonUI_SRCS
     Resources/ui/MeshRegion.ui
     Resources/ui/ResultHints.ui
     Resources/ui/ResultShow.ui
-    Resources/ui/SolverCalculix.ui
     Resources/ui/SolverCalculiX.ui
+    Resources/ui/SolverCcxTools.ui
 )
 
 ADD_CUSTOM_TARGET(FemPythonUi ALL

src/Mod/Fem/Gui/Resources/Fem.qrc

@@ -148,6 +148,7 @@
         <file>ui/MeshRegion.ui</file>
         <file>ui/ResultHints.ui</file>
         <file>ui/ResultShow.ui</file>
-        <file>ui/SolverCalculix.ui</file>
+        <file>ui/SolverCalculiX.ui</file>
+        <file>ui/SolverCcxTools.ui</file>
     </qresource>
 </RCC>

src/Mod/Fem/femtaskpanels/task_solver_ccxtools.py

@@ -56,7 +56,7 @@ class _TaskPanel:
 
     def __init__(self, solver_object):
         self.form = FreeCADGui.PySideUic.loadUi(
-            FreeCAD.getHomePath() + "Mod/Fem/Resources/ui/SolverCalculix.ui"
+            FreeCAD.getHomePath() + "Mod/Fem/Resources/ui/SolverCcxTools.ui"
         )
 
         from femtools.ccxtools import CcxTools as ccx