Feature Request: Support the ability to manage timezones in calendar widget

Hi there, I'm really enjoying using plasma-manager to manage my plasma desktop config. One challenge I'm facing is the constant resetting of timezones. I use the clock/calendar widget to show multiple timezones for a quick glance to see the times across countries. See screenshot <img width="790" height="460" alt="Image" src="https://github.com/user-attachments/assets/9967a4ef-5635-4dbe-991f-12258715e7df" /> However I can't yet see an option in plasma-manager. What that means though is after an update when plasma-manager updates I lose the selected timezones and need to manually re-select. I think the information is stored in `.config/plasma-org.kde.plasma.desktop-appletsrc`. For example, under: ``` ini [Containments][711][Applets][716][Configuration][Appearance] selectedTimeZones=America/Los_Angeles,America/Toronto,Local,Europe/London,Asia/Kolkata ``` I haven't found a graceful workaround as I can't modify a line in INI file easily. So I was hoping if I could put a feature request in to add the ability to configure this through plasma-manager. A complication I can see is the ID referenced for the location of the clock (711/716 in above example) but may be solvable given I define the panel layout and widgets in plasma-manager already.