more finegrained control regarding errored fields for user and developer

[bigmistqke]

At the moment validation-errors are only shown when the post is submitted during that visit. This is an acceptable pattern in the case of a small collection in which you have a clear overview of all the fields, but can become very unergonomic when working with bigger collections, for example a big collection existing out of multiple nested arrays combined with tabs.

Which one is it? To try to find your errored field only after you submitted can become a real horror-story: at the moment there is no other solution then to click your way through the complete collection.

I propose two possible enhancements to payload to address this issue:

1. give more finegrained control to the developer in when to display the error-messages, p.ex through:

• a parameter in the config-field: in which you can decide when the validation-errors are shown, p.ex "errorShown": "allways" | "after first blur" | "after submit"
• the return-value from the validation-function: returning a string would default to after submit, but with an object {message: "your error message", errorShown: "after first blur"} you get control over when the validation-error is shown.

2. give the errored fields-bar the functionality to focus to the errored fields, one by one.
   
   when you click the error-bar, the document would be scrolled to the errored field, if it is in a tab that is not visible, tab it would open this tab. If you click the error-bar again it would focus to the next errored field, etcetera. The error-bar would only countdown and dissapear once all the errored fields are solved.