Lack of feedback when editing autosaving fields

[sheepman4267]

OpenShow uses HTMX to auto-submit many editable fields, especially when editing segments. There's a lack of graphical feedback when the request is happening, though, making it very easy to discard edits by prematurely clicking the button to pull AOML into slides. This is always possible, but even more so on a slow internet connection

We need some kind of non-intrusive but obvious spinner to show up while HTMX is submitting form fields in the background.

• Deck Editor
• Show Editor
• Theme Editor
• Display Editor
• Transition Editor
• Media Editor
• Image Editor

[sheepman4267]

Fix implemented on deck editor in 0c48904.