Fix vendored nerdicons rendering; keep status bar always visible

- the vendored nerdicons.lua was the pristine upstream copy, so installs
  relying on the packaged plugin lost the tuned icon rendering (fractional
  glyph size and default hinting made icons feel soft and uneven). Apply
  the same tuning as the user config: whole-pixel icon size, hinting off,
  scale-aware chevron offset.
- default config (skel + first-run template) and this repo's users keep
  the status bar permanently visible: shown at startup, and the
  status-bar:hide/toggle commands are no-ops.

debian/extra/plugins/nerdicons.lua

@@ -55,7 +55,8 @@ config.plugins.nerdicons = common.merge({
   }
 }, config.plugins.nerdicons)
 
-local icon_font = renderer.font.load(nerdfonts_symbols.path, 18.5 * SCALE)
+local icon_font = renderer.font.load(nerdfonts_symbols.path, common.round(18.5 * SCALE),
+  {antialiasing = "grayscale", hinting = "none"})
 local map = nerdfonts_symbols.utf8
 local chevron_width = icon_font:get_width(map["oct-chevron_down"])
 local previous_scale = SCALE
@@ -186,7 +187,7 @@ function TreeView:draw_item_chevron(item, active, hovered, x, y, w, h)
     if item.type == "dir" then
       local chevron_icon = item.expanded and "oct-chevron_down" or "oct-chevron_right"
       local chevron_color = hovered and style.accent or style.text
-      common.draw_text(icon_font, chevron_color, map[chevron_icon], nil, x+8, y, 0, h) -- added 8 to x to draw the chevron closer to the icon
+      common.draw_text(icon_font, chevron_color, map[chevron_icon], nil, x + common.round(6 * SCALE), y, 0, h)
     end
     return chevron_width + style.padding.x
   end