Make settings editor launch robust

wezterm.lua

@@ -155,7 +155,15 @@ local function open_config_section(window, pane, line)
 			args = {
 				"sh",
 				"-lc",
-				string.format('editor="${EDITOR:-vi}"; exec "$editor" +%d %q', line, config_file),
+				string.format(
+					'file=%q; line=%d; editor="${VISUAL:-${EDITOR:-}}"; '
+						.. 'if [ -z "$editor" ]; then for candidate in nvim vim vi nano; do command -v "$candidate" >/dev/null 2>&1 && editor="$candidate" && break; done; fi; '
+						.. 'if [ -z "$editor" ]; then echo "No terminal editor found. Set EDITOR or install vim/nano."; exec "${SHELL:-sh}"; fi; '
+						.. '"$editor" +"$line" "$file"; status=$?; '
+						.. 'if [ $status -ne 0 ]; then echo; echo "Editor exited with status $status. Press Enter to close, or type commands below."; exec "${SHELL:-sh}"; fi',
+					config_file,
+					line
+				),
 			},
 		}),
 		pane