Fix Database Explorer tree expand hit target and side-button enablement on Windows

[leehaut]

Summary

• Fix unreliable expand/collapse of Catalogs/Tables/Views in DatabaseExplorerDialog on Windows (DPI/zoom misaligns the native > hit target; clicks often only worked in the tiny gap between > and the folder icon).

• Make folder interactions usable: gutter/icon clicks toggle expand when the native handler does nothing, and double-click on folders expands/collapses.

• Replace simple getters/setters with Lombok @Getter/@Setter; expand the Tables branch only after children are added.

[nadment]

The patch has unintended side effects on Windows: the arrows no longer work.

[leehaut]

The patch has unintended side effects on Windows: the arrows no longer work.

Thanks for reporting this. I'll reproduce the issue on Windows and work on a fix.

[leehaut]

@nadment Thanks for the report. I re-tested this on Windows several times (including clicking the tree expand/collapse arrows > / ∨, not only keyboard navigation), and expand/collapse behaves normally for me.

Could you share a bit more detail so I can try to reproduce it on my side?

• Hop version / build (or commit)
• Windows display scaling (100% / 125% / 150% …)
• Whether only the arrow is broken, or also folder-icon / double-click
• Any short screen recording if possible

Happy to follow up once I can reproduce it.

[nadment]

I made a short video to show the problem that occurs when I single click on the arrows for expand.
databaseexplorer_7765.zip

Version : hop-client-2.19.0-20260805.123340-1
Windows display scaling 100%
Hop UI zoom level: 150%

[nadment]

FYI, I'm also working on improving the database explorer.
#5376

[leehaut]

@nadment Thanks for the video and the extra details — that helped a lot.

I've prepared an initial fix for the Windows display-scaling / arrow expand issue. (#7811)

Also great to hear you're working on improving the Database Explorer in #5376. Looking forward to your changes! 😊