Reconsider auto-suggest text box

[pinussilvestrus]

Originally posted by @pinussilvestrus in bpmn-io/bpmn-properties-panel#54 (comment)

Inside the old properties panel, we created a first iteration of what we call "auto-suggest text component" - only used by input/output parameter expressions. The question for me would be whether we want to spend time rebuilding this thing. I'd vote for no and tackle it at a later point in time because

• it was really just a first iteration and there is much room for improvement
• it would take us time to build this "hack" again
• it would take us more time right now to build a proper autocomplete (concept + implementation)
• we plan to maybe have a proper code editor/syntax highlighting component anyway in the future (at least we had it once in our OKRs)
• we don't know yet how much this single input was actually used

What should we do?

Bring the auto-suggest text box once we see a need. Also cf.

• Autosuggest: Close expression after applying a suggested variable #378
• Add Keyboard Navigation to auto-suggest textbox #362
• https://github.com/bpmn-io/internal-docs/issues/182

Why should we do it?

Auto suggesting process variables makes it way easier to create valid expressions.