Revise C++ coding style using clang-format with "east const"

Run the `clang-format.bash` script to update all our C and C++ code to a
new style defined by `.clang-format`, now with "east const" enforcement.
Use `clang-format` version 18.

* If you reached this commit for a line in `git blame`, re-run the blame
  operation starting at the parent of this commit to see older history
  for the content.

* See the parent commit for instructions to rebase a change across this
  style transition commit.

Issue: #26123

Help/guide/tutorial/Step8/tutorial.cxx

@@ -17,9 +17,9 @@ int main(int argc, char* argv[])
   }
 
   // convert input to double
-  const double inputValue = std::stod(argv[1]);
+  double const inputValue = std::stod(argv[1]);
 
-  const double outputValue = mathfunctions::sqrt(inputValue);
+  double const outputValue = mathfunctions::sqrt(inputValue);
 
   std::cout << "The square root of " << inputValue << " is " << outputValue
             << std::endl;