home: vim: configure diagnostics further

This is not only 'lsp_lines' configuration anymore, but the whole
display of diagnostics.

home/vim/plugin/settings/diagnostics.vim

@@ -0,0 +1,17 @@
+lua << EOF
+-- Show LSP diagnostics on virtual lines over affected regions
+require("lsp_lines").register_lsp_virtual_lines()
+
+vim.diagnostic.config({
+    -- Disable virtual test next to affected regions
+    virtual_text = false,
+    -- Show diagnostics signs
+    signs = true,
+    -- Underline offending regions
+    underline = true,
+    -- Do not bother me in the middle of insertion
+    update_in_insert = false,
+    -- Show highest severity first
+    severity_sort = true,
+})
+EOF

home/vim/plugin/settings/lsp_lines.vim

@@ -1,9 +0,0 @@
-lua << EOF
--- Show LSP diagnostics on virtual lines over affected regions
-require("lsp_lines").register_lsp_virtual_lines()
-
--- Disable virtual test next to affected regions
-vim.diagnostic.config({
-  virtual_text = false,
-})
-EOF