feat(extras): added simple csharp extra

lua/lazyvim/plugins/extras/lang/omnisharp.lua

@@ -0,0 +1,51 @@
+return {
+  { "Hoffs/omnisharp-extended-lsp.nvim", lazy = true },
+  {
+    "nvim-treesitter/nvim-treesitter",
+    opts = function(_, opts)
+      if type(opts.ensure_installed) == "table" then
+        vim.list_extend(opts.ensure_installed, { "c_sharp" })
+      end
+    end,
+  },
+  {
+    "jose-elias-alvarez/null-ls.nvim",
+    opts = function(_, opts)
+      local nls = require("null-ls")
+      table.insert(opts.sources, nls.builtins.formatting.csharpier)
+    end,
+  },
+  {
+    "williamboman/mason.nvim",
+    opts = function(_, opts)
+      opts.ensure_installed = opts.ensure_installed or {}
+      table.insert(opts.ensure_installed, "csharpier")
+    end,
+  },
+  {
+    "neovim/nvim-lspconfig",
+    opts = {
+      servers = {
+        omnisharp = {
+          handlers = {
+            ["textDocument/definition"] = function(...)
+              return require("omnisharp_extended").handler(...)
+            end,
+          },
+          keys = {
+            {
+              "gd",
+              function()
+                require("omnisharp_extended").telescope_lsp_definitions()
+              end,
+              desc = "Goto Definition",
+            },
+          },
+          enable_roslyn_analyzers = true,
+          organize_imports_on_format = true,
+          enable_import_completion = true,
+        },
+      },
+    },
+  },
+}