[explore]Improve Experience of adding chart to NEW dashboard from Explore

[zuzana-vej]

Is your feature request related to a problem? Please describe.

The current experience of adding chart from Explore to a NEW dashboard is confusing for some users.

In the textbox, it says "Select a dashboard OR create a new one" but it's not apparent to users that all they need to do is type a new dashboard name, press enter, and then the "Save & go to dashboard" button will be enabled. User thought this was a bug.

Describe the solution you'd like
In the past, there used to be a "Create new dashboard option" from the dropdown and it opened up a dialog box to type a dashboard name - also slightly clunky. Maybe if the text said something like "Type new dashboard name here or select from existing". There just needs to be some signal that it's type-able.

Describe alternatives you've considered
Few options:

1. easiest: Better text in the text field - for example "Type new dashboard name here or select from existing"
2. button create new dashboard, which opens a popup where user fills new dashboar details (apparently past solution)
3. tooltip, letting user know to "Type new dashboard name and click enter"

[junlincc]

it's not apparent to users that all they need to do is type a new dashboard name, press enter, and then the "Save & go to dashboard" button will be enabled.

suffering from the same confusion here 😞 we may have to go with the easiest solution for now. tag design-sys-revisit

@mihir174

[ktmud]

Related #10355

[mihir174]

Here's a common pattern for saving to a new instance: