feat(11-01): run job workers in serve and queue:work, add queue:clear

- Manager gains the apparatus JobManager surface: StartJob, UpdateJobState,
  UpdateMetadata, FailJob, CancelJob (is_canceled + STOPPED + River JobCancel),
  StopJob (STOPPED only), CheckIfCanceled and GetMetadata, all raw column
  writes so updated_at is untouched
- serve starts the in-process worker unless queue.work_in_serve is false and
  stops it on shutdown; an app without jobs gets an idle worker
- queue:work runs a foreground worker with repeatable --queue filters;
  queue:clear deletes available, scheduled and retryable jobs of one queue
- the generated main appends conga.RuntimeCommands; summer delegates
  queue:work and queue:clear; make:job scaffolds a conga.Job

internal/build/build_test.go

@@ -128,6 +128,20 @@ func TestGenerateMainRegistersCabanaRuntimeCommands(t *testing.T) {
 	}
 }
 
+func TestGenerateMainRegistersCongaRuntimeCommands(t *testing.T) {
+	mainSrc, err := generateMain(Manifest{Module: "example.com/app", Binary: "hello"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	line := []byte("commands = append(commands, conga.RuntimeCommands(app, plugins)...)")
+	if n := bytes.Count(mainSrc, line); n != 1 {
+		t.Fatalf("conga.RuntimeCommands line count = %d, want 1\n%s", n, mainSrc)
+	}
+	if !bytes.Contains(mainSrc, []byte(`"git.golem15.com/golem15/summercms/modules/conga"`)) {
+		t.Fatalf("generated main does not import conga:\n%s", mainSrc)
+	}
+}
+
 func TestWriteIfChangedSkipsIdenticalBytes(t *testing.T) {
 	dir := t.TempDir()
 	path := filepath.Join(dir, "out.go")
@@ -696,9 +710,9 @@ func TestScaffoldAllArtifacts(t *testing.T) {
 	for _, want := range []string{
 		"func (ReindexArgs) Kind()",
 		`Kind() string { return "golem15.demo.reindex" }`,
-		"func (reindexJob) Work(",
-		"unexpected args type",
-		"func ReindexJob()",
+		"func ReindexJob() pact.Job",
+		"conga.Job(func(ctx context.Context, args ReindexArgs) error",
+		`"git.golem15.com/golem15/summercms/modules/conga"`,
 	} {
 		if !bytes.Contains(jobSrc, []byte(want)) {
 			t.Fatalf("job.go missing %s:\n%s", want, jobSrc)