[Feature Request] graphical UI for streamline_template creation-modification

[BBE-FR]

Hello,

Maybe there is an existing way around this, but I did not find it.

I am a user of the UI, and rather YAML reluctant although I am able to use it. I really like to be able to see rather directly the change I made, and find the UI easier for a quick access to a dedicated parameter / part of a card. (I might be marginal around the user of streamline card, I recognize it...).

I really appreciate the graphical UI that is available to add/edit streamline-cards in the dashboard view:

But nothing is available for the template creation and modification

Thus, to create a streamline card, I follow this path:

• I start with implementing a card in UI, with working entities to initiate it, in a "sandbox" view.
• Then I copy paste the YAML of the card into a streamline_template into the yaml of the dashboard.
• Then I replace the entities one by one by the associated <variable_name>

The point I struggle the most is after this creation time, when I need to modify a card:

• You need to scroll a lot down the YAML to find back the right template card and modify it
• you have no preview of your modification to test your work.
• you need to create a streamline-card with defined variable in a view
• you do multiple changes between YAML edition of the streamline-template and visualisation of your changes in the view to cross check your modifications

Would there be a way to use a graphical UI to do this work?

• once the streamline_template is created, to visualise and modify it?
• once available, the "creation" part should be similar

I recognize it doesn't seem easy, but it would be very practical, a good evolution toward a more graphical use of home assistant and make streamline-card more accessible to a huge number of users.
Many are requesting a kind of "master cards" that you could copy paste into your dashboard in order to modify one card and propagate the changes everywhere into "copied cards"...

It could make a deep use of the default-variable to display the same kind of render as the one used in the dashboard UI when using streamline card once defined.

Exemple of possible interface to access the templates (it could be rendered as a view):

Exemple of card template modification interface (close to the dasboard one, but with possibility to edit the template itself):

As a first step, an edition in YAML only would already be very nice.
As a final step, UI editor would be 100% professional like !!

Thanks again for the great job already done.

Regards
BBE