Quick fix for adding parameter/variable for missing variable

**Is your feature request related to a problem? Please describe.**
When introducing a new variable i would like a quick fix to add a new param/var with the same name.
Starting with a new bicep file, adding resource that needs location, writing location: location, ctrl + . and not see Add new param = 😢.

**Describe the solution you'd like**
Add option in ctrl + '.' to Add new param and Add new variable for vs code extension.

The issue identifies the VS Code extension and Ctrl+. quick-fix flow, but no files or tests. Start by locating the quick-fix or code-action implementation for missing variables, then determine how its available actions are tested. Done means Ctrl+. offers both “Add new param” and “Add new variable” for a missing variable.

Written by the indexing model from the issue text.