Improve spell checker using codespell

* Configures automated spell checking with codespell
Adds GitHub workflows and configuration files for automated spell checking using `codespell`.

This includes:
- A workflow for checking pull requests and preventing new typos
- A workflow for automatically fixing typos in the main codebase
- Configuration files for `codespell` to ignore specific terms and file types
- Documentation on how to use and configure the spell checking workflows.

* Corrects minor spelling and grammar errors.

ApplicationLibCode/ProjectDataModel/Flow/RimWellConnectivityTable.cpp

@@ -386,7 +386,7 @@ void RimWellConnectivityTable::fieldChangedByUi( const caf::PdmFieldHandle* chan
             setWellSelectionFromViewFilter();
         }
 
-        // For singe time step - no apply buttons due to low computation time
+        // For single time step - no apply buttons due to low computation time
         onLoadDataAndUpdate();
     }
     else if ( changedField == &m_selectedFromTimeStep || changedField == &m_selectedToTimeStep ||