Activation app picker doesn't include apps outside of /Applications

Reproduction steps

1. Open the Settings pane.

2. Click on any of the Edit buttons in the Modes section.

3. Click on the + button under Activation Apps.

4. TypeActivity Monitor.

Expected results

The list of applications is narrowed to include only Activity Monitor.

Actual results

Activity Monitor is not shown.

Notes

It appears that only applications in /Applications are shown. Applications in subdirectories within /Applications, for example /Applications/Utilities or /Applications/Nix Apps (where Home Manager installs apps), are not shown.