Add GNOME 46 to supported shell versions

[birgersp]

Summary

• Add GNOME Shell 46 to the supported versions list in metadata.json.

Rationale

• The extension runs on GNOME 46 with the existing ES module–based code.
• Having 46 in metadata.json allows installation from extensions.gnome.org on that release.

Testing

• GNOME Shell 46.x: hotkey launches switcher, window/app search works, prefs dialog opens.

(fixes #185)

[birgersp]

Actually looks like there are some small issues with the code on v 46. I will try to fix them so it works for v 46 as well.

[birgersp]

Here is the issue; selected entry isn't visuall highlighted (colored in a brighter color):

Fixed:

commit incoming