fix: stop modal appearing in steps (#43728)

* fix: stop showing completion modal on steps

* feat: submit steps with ctrl+enter

* fix: handle ctrl+enter when not focussing editor

* fix: reset tests when user types

* refactor: pass showCompletionModal as an option

Otherwise we have to write executeChallenge(true) which does not mean
what you might reasonably expect.

* fix: always executeChallenge when not on step

* fix: update frontend project show

* fix: handle missing payload

* refactor: isProjectStep -> hasEditableRegion

* refactor: more renaming

* fix: make meta.json control multifile editor use

* fix: update the challengeSchema correctly

* Update client/src/templates/Challenges/classic/editor.tsx

Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>

* fix: remove logging

Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>

Co-authored-by: Shaun Hamilton <shauhami020@gmail.com>

curriculum/schema/challengeSchema.js

@@ -111,7 +111,8 @@ const schema = Joi.object()
     url: Joi.when('challengeType', {
       is: challengeTypes.codeally,
       then: Joi.string().required()
-    })
+    }),
+    usesMultifileEditor: Joi.boolean()
   })
   .xor('helpCategory', 'isPrivate');