* feat: add WithTemplate page
* app/vmselect/prometheus: enable json mode for expand with expr API
* app/vmselect/prometheus: enable CORS and add content type
* feat: add api for expand with templates
* fix: remove console from useExpandWithExprs
* app/vmselect/prometheus: fix escaping
* vmui: integrate WITH template
* app/vmctl: check content type instead of form param
* fix: add content-type for fetch with-exprs
* fix: add a header to the server's response that allows the "Content-Type" header
* app/vmctl: added comment and cleanup
* app/vmctl: use format query param
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Co-authored-by: dmitryk-dk <kozlovdmitriyy@gmail.com>