nvim: rework lsp_sig_status()

.config/nvim/lua/my/functions.lua

@@ -140,11 +140,24 @@ function M.lsp_status()
 end
 
 function M.lsp_sig_status()
+    if not vim.lsp.buf.server_ready() then
+        return ""
+    end
+
     local width = vim.o.columns / 3
+    if width < 40 then
+        return ""
+    end
     if width > 50 then
         width = width * 1.5
     end
-    return require('lsp_signature').status_line(width).label
+
+    local label = require('lsp_signature').status_line().label
+    if label:len() > width then
+        label = label:sub(1, width) .. '…'
+    end
+
+    return label
 end
 
 function M.not_firenvim()