Refactored file structure to make more sense, made default.nixes less verbose

modules/sys/software/nixvim/plugins/vim-matchup.nix

@@ -0,0 +1,23 @@
+{
+  programs.nixvim = {
+    plugins.vim-matchup = {
+      enable = true;
+      enableSurround = true;
+      textObj.enable = true;
+      motion = {
+        enable = true;
+        cursorEnd = true;
+      };
+      matchParen = {
+        hiSurroundAlways = true;
+        offscreen = {
+          method = "popup";
+        };
+      };
+      treesitterIntegration = {
+        enable = true;
+        includeMatchWords = true;
+      };
+    };
+  };
+}