modules: start breaking down core modules; simplify tree structure

modules/plugins/ui/modes/config.nix

@@ -0,0 +1,30 @@
+{
+  config,
+  lib,
+  ...
+}: let
+  inherit (lib) mkIf nvim boolToString;
+
+  cfg = config.vim.ui.modes-nvim;
+in {
+  config = mkIf cfg.enable {
+    vim.startPlugins = [
+      "modes-nvim"
+    ];
+
+    vim.luaConfigRC.modes-nvim = nvim.dag.entryAnywhere ''
+      require('modes').setup({
+        set_cursorline = ${boolToString cfg.setCursorline},
+        line_opacity = {
+          visual = 0,
+        },
+        colors = {
+          copy = "${toString cfg.colors.copy}",
+          delete = "${toString cfg.colors.delete}",
+          insert = "${toString cfg.colors.insert}",
+          visual = "${toString cfg.colors.visual}",
+        },
+      })
+    '';
+  };
+}