chore(core): wrap initial state into hidden container

[ShGKme]

Summary

Sometimes it's quite annoying during debug that there are tons of elements in the document's root for initial state.

I propose to wrap it in a hidden container.

Before	After

TODO

• Wrap all <input id="initial-state-..." /> into a hidden div container
• Move it to a new file for reuse

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)