pkg/terminal: support zed editor and allow args in DELVE_EDITOR (#3899)

Enhance editor support for the DELVE_EDITOR environment variable

1. Add support for the Zed editor by recognizing the 'zed' command and setting
   the appropriate line number syntax

2. Allow users to specify editor-specific arguments in DELVE_EDITOR by parsing
   the env var value into command and args parts

3. Modify runEditor() to pass through any user-specified args before appending
   the file/line args

This change allows more configuration flexibility through DELVE_EDITOR while
maintaining backwards compatibility. The Zed editor is now supported alongside
VSCode, Helix and Vim variants.

Fixes #3627

pkg/terminal/command.go

@@ -1960,22 +1960,32 @@ func tracepoint(t *Term, ctx callContext, args string) error {
 	return err
 }
 
-func getEditorName() (string, error) {
+func getEditorName() (string, []string, error) {
 	var editor string
 	if editor = os.Getenv("DELVE_EDITOR"); editor == "" {
 		if editor = os.Getenv("EDITOR"); editor == "" {
-			return "", errors.New("Neither DELVE_EDITOR or EDITOR is set")
+			return "", nil, errors.New("Neither DELVE_EDITOR or EDITOR is set")
 		}
 	}
-	return editor, nil
+
+	editorParts := strings.Fields(editor)
+	editor = editorParts[0]
+
+	var userArgs []string
+	if len(editorParts) > 1 {
+		userArgs = editorParts[1:]
+	}
+
+	return editor, userArgs, nil
 }
 
 func runEditor(args ...string) error {
-	editor, err := getEditorName()
+	editor, userArgs, err := getEditorName()
 	if err != nil {
 		return err
 	}
-	cmd := exec.Command(editor, args...)
+	allArgs := append(userArgs, args...)
+	cmd := exec.Command(editor, allArgs...)
 	cmd.Stdin = os.Stdin
 	cmd.Stdout = os.Stdout
 	cmd.Stderr = os.Stderr
@@ -1987,13 +1997,15 @@ func edit(t *Term, ctx callContext, args string) error {
 	if err != nil {
 		return err
 	}
-	editor, err := getEditorName()
+	editor, _, err := getEditorName()
 	if err != nil {
 		return err
 	}
 	switch editor {
 	case "code":
 		return runEditor("--goto", fmt.Sprintf("%s:%d", file, lineno))
+	case "zed":
+		return runEditor(fmt.Sprintf("%s:%d:0", file, lineno))
 	case "hx":
 		return runEditor(fmt.Sprintf("%s:%d", file, lineno))
 	case "vi", "vim", "nvim":