Add keymaps and settings for nixvim plugins

- Add Conform auto-format document keymap in conform.nix
- Enable and configure Oil plugin settings in oil.nix
- Update Telescope keymaps definition in telescope.nix

home/common/core/nixvim/plugins/conform.nix

@@ -38,4 +38,16 @@
     }
 
   '';
+  programs.nixvim.keymaps = [
+    # format document with Conform
+    {
+      mode = ["n"];
+      key = "<leader>cf";
+      action = "<CMD>Format<CR>";
+      options = {
+        silent = true;
+        desc = "Conform auto-format document";
+      };
+    }
+  ];
 }

home/common/core/nixvim/plugins/oil.nix

@@ -1,5 +1,9 @@
 {
   programs.nixvim.plugins.oil = {
     enable = true;
+    settings = {
+      columns = ["icon"];
+      view_options.show_hidden = true;
+    };
   };
 }

home/common/core/nixvim/plugins/telescope.nix

@@ -3,7 +3,7 @@
     enable = true;
     extensions.fzy-native.enable = true;
   };
-  keymaps = [
+  programs.nixvim.keymaps = [
     {
       # find files
       mode = ["n"];