Breaking change for statusline_separator field users | optimize statusline & make it overridable

added cmd fields for various plugins for example lspinstaller+lspconfig gets loaded only when a file opened but their commands can be run before a file is opened so I additionally lazy loaded them on their cmds too

lua/ui/icons.lua

@@ -40,6 +40,28 @@ M.lspkind = {
    Package = "",
 }
 
+M.statusline_separators = {
+   default = {
+      left = "",
+      right = " ",
+   },
+
+   round = {
+      left = "",
+      right = "",
+   },
+
+   block = {
+      left = "█",
+      right = "█",
+   },
+
+   arrow = {
+      left = "",
+      right = "",
+   },
+}
+
 M.devicons = {
    default_icon = {
       icon = "",