Adjust left panel styling

User feedback says that the map needs more space / prominence. We could reduce the width of the panel and the text size. Some uncertainty whether the main tool buttons the user switches between should stay the current size or also shrink. Relatedly, one of the design principles I've learned in NPW has me noticing the lack of padding in the left panel generally -- a bit could help.

Look for the left panel styling in the frontend code, likely in CSS or Rust UI files. Identify the current width, text size, and padding values. Experiment with reducing panel width and text size, and adding padding, while considering the size of the main tool buttons. Test changes in the browser to see the effect on map prominence and overall layout.

Written by the indexing model from the issue text.