Minor automation form polish #28

Problem #

Small items from the same session:

• The "ACTION 3 #2" header is confusing (ActionHeader/index.tsx:55).
• No warning when the action's target collection equals the trigger collection, which can loop (seen at 0:38).
• The overview flow strip collapses multiple steps to one icon.

Seen in the session #

In https://www.youtube.com/watch?v=5MnT-ZgbBIc:

• Throughout.

Details: docs/brainstorms/2026-10-17-graze-conference-automation-feedback.md (U13).

Update #

The schema-not-found alert that flashed while typing a partial NSID moved to #46, where it also blurs the input.