feat(04-01): generate jobs and admin controllers, reject model imports

Scaffold pact.Job and pact.AdminController stubs with Winter YAML
assets, and fail summer build when models imports a sibling package.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/build/artifact.go

@@ -24,6 +24,9 @@ type artifactData struct {
 	Ident       string
 	Table       string
 	Func        string
+	Worker      string
+	Kind        string
+	ConfigDir   string
 	MigrationID string
 	UpSQL       string
 	DownSQL     string
@@ -187,6 +190,124 @@ func MakeCommand(ctx context.Context, startDir, pluginID, name string) (Artifact
 	return ArtifactResult{PluginDir: plugin.Dir, Files: []string{path}, Hint: plugin.Hint}, nil
 }
 
+// MakeJob writes a pact.Job stub without importing River.
+func MakeJob(ctx context.Context, startDir, pluginID, name string) (ArtifactResult, error) {
+	plugin, err := resolvePlugin(startDir, pluginID)
+	if err != nil {
+		return ArtifactResult{}, err
+	}
+	if err := validateExportedIdent(name); err != nil {
+		return ArtifactResult{}, fmt.Errorf("build: job: %w", err)
+	}
+	fn := name + "Job"
+	if err := rejectDuplicateIdent(plugin.Dir, "jobs", fn); err != nil {
+		return ArtifactResult{}, err
+	}
+	rel := filepath.Join("jobs", toSnake(name)+".go")
+	if err := rejectDuplicateFile(plugin.Dir, rel); err != nil {
+		return ArtifactResult{}, err
+	}
+	src, err := renderStub("job.go", artifactData{
+		Ident:  name,
+		Func:   fn,
+		Worker: unexportedIdent(name) + "Job",
+		Kind:   plugin.ID + "." + toSnake(name),
+	})
+	if err != nil {
+		return ArtifactResult{}, err
+	}
+	path := filepath.Join(plugin.Dir, rel)
+	if err := writeFile(path, src); err != nil {
+		return ArtifactResult{}, err
+	}
+	if err := finishArtifact(ctx, plugin); err != nil {
+		os.Remove(path)
+		return ArtifactResult{}, err
+	}
+	return ArtifactResult{PluginDir: plugin.Dir, Files: []string{path}, Hint: plugin.Hint}, nil
+}
+
+// MakeAdminController writes a pact.AdminController and Winter-shaped YAML.
+func MakeAdminController(ctx context.Context, startDir, pluginID, name string) (ArtifactResult, error) {
+	plugin, err := resolvePlugin(startDir, pluginID)
+	if err != nil {
+		return ArtifactResult{}, err
+	}
+	if err := validateExportedIdent(name); err != nil {
+		return ArtifactResult{}, fmt.Errorf("build: admin-controller: %w", err)
+	}
+	fn := name + "Controller"
+	if err := rejectDuplicateIdent(plugin.Dir, "controllers", fn); err != nil {
+		return ArtifactResult{}, err
+	}
+	snake := toSnake(name)
+	rel := filepath.Join("controllers", snake+".go")
+	if err := rejectDuplicateFile(plugin.Dir, rel); err != nil {
+		return ArtifactResult{}, err
+	}
+	configDir := filepath.ToSlash(filepath.Join("controllers", snake))
+	fieldsRel := filepath.Join("controllers", snake, "fields.yaml")
+	columnsRel := filepath.Join("controllers", snake, "columns.yaml")
+	for _, yamlRel := range []string{fieldsRel, columnsRel} {
+		if err := rejectDuplicateFile(plugin.Dir, yamlRel); err != nil {
+			return ArtifactResult{}, err
+		}
+	}
+	src, err := renderStub("admin_controller.go", artifactData{
+		Ident:     name,
+		Func:      fn,
+		Worker:    unexportedIdent(name) + "Admin",
+		Kind:      plugin.ID + "." + snake,
+		ConfigDir: configDir,
+	})
+	if err != nil {
+		return ArtifactResult{}, err
+	}
+	fieldsSrc, err := renderStub("fields.yaml", nil)
+	if err != nil {
+		return ArtifactResult{}, err
+	}
+	columnsSrc, err := renderStub("columns.yaml", nil)
+	if err != nil {
+		return ArtifactResult{}, err
+	}
+
+	var created []string
+	rollback := true
+	defer func() {
+		if rollback {
+			for _, path := range created {
+				os.Remove(path)
+			}
+		}
+	}()
+	goPath := filepath.Join(plugin.Dir, rel)
+	if err := writeFile(goPath, src); err != nil {
+		return ArtifactResult{}, err
+	}
+	created = append(created, goPath)
+	fieldsPath := filepath.Join(plugin.Dir, fieldsRel)
+	if err := writeFile(fieldsPath, fieldsSrc); err != nil {
+		return ArtifactResult{}, err
+	}
+	created = append(created, fieldsPath)
+	columnsPath := filepath.Join(plugin.Dir, columnsRel)
+	if err := writeFile(columnsPath, columnsSrc); err != nil {
+		return ArtifactResult{}, err
+	}
+	created = append(created, columnsPath)
+	if err := finishArtifact(ctx, plugin); err != nil {
+		return ArtifactResult{}, err
+	}
+	rollback = false
+	return ArtifactResult{PluginDir: plugin.Dir, Files: created, Hint: plugin.Hint}, nil
+}
+
+func unexportedIdent(name string) string {
+	r, size := utf8.DecodeRuneInString(name)
+	return string(unicode.ToLower(r)) + name[size:]
+}
+
 type pluginRef struct {
 	Dir  string
 	ID   string