chore(nvim): remove unused files

modules/coding/editor/neovim/nvim/lua/plugins/lsp/signature.lua

@@ -1,19 +0,0 @@
-M = {
-  bind = true, -- This is mandatory, otherwise border config won't get registered.
-  handler_opts = {
-    border = "rounded",
-  },
-  hint_prefix = "^ ",
-  toggle_key = "<C-k>",
-}
-
-vim.keymap.set(
-  { "n" },
-  "<leader>k",
-  require("lsp_signature").toggle_float_win,
-  { silent = true, noremap = true, desc = "toggle signature" }
-)
-
-vim.keymap.set({ "n" }, "K", vim.lsp.buf.signature_help, { silent = true, noremap = true, desc = "toggle signature" })
-
-return M