Make inputs commit on blur, and let browser handle undo/redo

[barmac]

Make inputs commit on blur, and have a separate command stack (browser native) instead of diagram-js command stack.

Originally posted by @barmac in #852 (comment)

Describe the Bug

Right now the inputs commit to the command stack which results in:

1. Slow input undo/redo
2. You can undo changes outside of the input from that input

Steps to Reproduce

Steps to reproduce the behavior:

1. Type in literal expression
2. Cmd/Ctrl + Z

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Expected Behavior

Browser and code editor library handle inputs while command stack handles all the rest. Single undo outside of the input undoes the entire input change.

Environment

Please complete the following information:

• Browser: [e.g. IE 11, Chrome 69]
• OS: [e.g. Windows 7]
• Library version: [e.g. 2.0.0]

[barmac]

Additional context:

There is a difference between how change events are handled in text inputs and contenteditable elements. For a text input, you can listen to a change event which is dispatched only on blur and if input value was changed. In contrast, contenteditable does not fire the change event, and a common solution is to listen to the input . However, it behaves differently as input event is dispatched after each keystroke. In a naive implementation of contenteditable, we may flood the editor command stack with changes which leads to a problems like in #859
https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement/change_event

https://camunda.slack.com/archives/GP70M0J6M/p1715331428555569

[barmac]

The FEEL editor relies on CodeMirror's updateListener to call the change handler. However, such updates behave much more closely to the browser input events, as the handler is called each time the editor view updates. This is way too often, so in the LiteralExpression component we should emulate browser's change event behavior, i.e. call the handler only on blur when the value changed.

[nikku]

We could consider to change the FEEL editor change handler once we settled on unifying the behavior.

[barmac]

Agreed, but that means a breaking change if we modify the onChange callback behavior.