Lock individual items

Hello, i appreciate that we have a read-only mode on mobile, but recently i wondered, what if we went a step further? I have a few items in my notes that are always fixed and would like to protect them from accidental editing or deletion.

So, i think it would be very useful if there was a function to lock an individual item (and optionally its children). This would prevent any further edits to their text content and parent/child relationships. However, i would still like to be able to check/uncheck locked items.