Extend mdspan interface and fix mdspan memory layout mapping

This MR fixes the way memory layouts for std::mdspan are modelled and inferred.

• Add the layout_policy template parameter to the StdMdspan class.
• Use layout_strided by default (cannot infer layout from field instance, because of pystencils#117)
• Extend mdspan AugExpr interface
• Extend mdspan documentation
• Add test cases for checking shape and strides of mdspans created from fixed-shape fields
• Add test cases for checking shape and strides of mdspans created from var-shape fields

src/pystencilssfg/emission/clang_format.py

@@ -29,7 +29,8 @@ def invoke_clang_format(code: str, options: ClangFormatOptions) -> str:
 
     binary = options.get_option("binary")
     force = options.get_option("force")
-    args = [binary, f"--style={options.code_style}"]
+    style = options.get_option("code_style")
+    args = [binary, f"--style={style}"]
 
     if not shutil.which(binary):
         if force: