refactor: include the signature help plugin

lua/plugins/coding.lua

@@ -37,6 +37,7 @@ return {
             "hrsh7th/cmp-buffer",
             "hrsh7th/cmp-path",
             "saadparwaiz1/cmp_luasnip",
+            "hrsh7th/cmp-nvim-lsp-signature-help",
         },
         opts = function()
             vim.api.nvim_set_hl(0, "CmpGhostText", { link = "Comment", default = true })
@@ -62,6 +63,7 @@ return {
                     { name = "nvim_lsp" },
                     { name = "buffer", keyword_length = 5 },
                     { name = "luasnip", keyword_length = 3 },
+                    { name = "nvim_lsp_signature_help" },
                 }),
             }
         end,