applets/weather: Fix layout for large station names

The layout minimum width was unconditionally dependent of the station name, which in some extreme cases, could overflow the strict width set by the system tray.

Put a maximum cap to this minimum width and elide the label if necessary.

This has benefits also on the other form factors (desktop and free in the panel), as one can now reduce the applet's width even for very large station names, but keeps the preferred size and allows full customizability.

Testing

Search for American airports 😄

Bug fixed

No bug reports currently, but I think there were some at some point

Screenshots

BEFORE	AFTER