optimize Developer tools

[Mariusthvdb]

As a followup of Discord discussion #beta 2021.6 please consider optimizing the Developer tools page/tabs.

On a fully loaded system with many entities, the default /state page takes a long time to load, and become truly responsive for entering filtering strings (even on desktop, which is needed for viewing attributes column, which is not there on mobile.) one even has to wait for that when in need of the /template or other tabs

Probably the easiest/quickest fix would be loading the /template page by default, instead of the /state

Discussion suggested the /state page would be optimized too, but I am no dev so wouldn't know how to start with that invitation...

please consider?

[BoneheadFraggle]

Or loading the /state page, but with all entities filtered out at first so you instead need to enter something (for example using the new very nice wildcards)
A simple * would show you everything you see today, and all other times you open the page you would save time :-)

[emufan]

This!

[GrizzlyAK]

Speaking of the /template page, it would be great if the RESET TO DEMO TEMPLATE button was replaced with a CLEAR button. Or better yet, just ADD a CLEAR button to the page. The CLEAR button could place the cursor in the newly emptied box ready for a paste or typing.