editor: Fix gutter tooltip modifier hint (#64124)

# Objective

Fixes #58821. Follow-up to #58880: keep the modifier-click hint accurate
when the tooltip switches from breakpoint to bookmark.

## Solution

Build the hint from the configured secondary gutter action instead of
the currently active action.

## Self-Review Checklist

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content adheres to Zed's UI standards
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

## Showcase



https://github.com/user-attachments/assets/c514d30e-9747-40a1-b359-54bc10086366

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Release Notes:

- Fixed the gutter tooltip's modifier-click hint after holding Command.
a2651e3b56Gautam Manchandani committed on 9/12/2026, 5:16:02 PM· committed by GitHubparent9d272b0
2 files changedLine totals unavailable