Add GSP links field and link inspection

toolkit/cmd/gsp/main.go

@@ -48,6 +48,8 @@ func run(args []string) error {
 		return runFlatten(args[1:])
 	case "pack":
 		return runPack(args[1:])
+	case "links":
+		return runLinks(args[1:])
 	case "impact":
 		return runImpact(args[1:])
 	case "message":
@@ -78,6 +80,7 @@ Usage:
   gsp trace <id> [--root .] [--depth 3] [--out trace.json]
   gsp flatten <id> [--root .] [--depth 3] [--include-type a,b] [--exclude-type a,b] [--out flattened.json]
   gsp pack <id> [--root .] [--for implement] [--stage implement] [--depth 3] [--budget 12000] [--format json|md|canvas] [--out context-pack.json]
+  gsp links <id> [--root .] [--depth -1] [--format json|md] [--out links.json]
   gsp impact <id> [--root .] [--depth -1] [--format json|md|canvas] [--out impact.json]
   gsp message validate <file> [--root .] [--out message-report.json]
   gsp graph [id] [--root .] [--depth 3] [--format json|mermaid|md|canvas] [--out graph.json]
@@ -85,6 +88,33 @@ Usage:
 `)
 }
 
+func runLinks(args []string) error {
+	fs := flag.NewFlagSet("links", flag.ContinueOnError)
+	root := commonRoot(fs)
+	out := commonOut(fs)
+	depth := fs.Int("depth", -1, "maximum relation depth; -1 means unlimited")
+	format := fs.String("format", "json", "json or md")
+	if err := fs.Parse(normalizeFlagArgs(args)); err != nil {
+		return err
+	}
+	if fs.NArg() != 1 {
+		return fmt.Errorf("links requires one GSP id")
+	}
+	project, err := gsp.LoadProject(*root)
+	if err != nil {
+		return err
+	}
+	result := project.Links(fs.Arg(0), *depth)
+	switch *format {
+	case "json":
+		return writeJSON(*out, result)
+	case "md":
+		return writeText(*out, result.Markdown())
+	default:
+		return fmt.Errorf("unsupported links format %q", *format)
+	}
+}
+
 func runCompletion(args []string) error {
 	if len(args) == 0 {
 		return fmt.Errorf("completion requires powershell, bash, zsh, fish, or install powershell")