feat(P04): --pprof opt-in on orca daemon (REQ-056, I-308)

Separate *http.Server + *http.ServeMux (AD-024), default disabled.
Operator opts in via --pprof <addr>. WARN logged on startup. All pprof
handlers explicitly registered on dedicated mux (no DefaultServeMux
side-effect). I-308 deferred since v0.2 now implemented. 6 new tests.

---ci---
project: orca
phase: 4
milestone: v0.7
status: verify
requirements:
  covered: [REQ-056]
  partial: []
---/ci---

internal/cli/daemon.go

@@ -20,6 +20,7 @@ import (
 
 var (
 	daemonAddr string
+	pprofAddr  string
 )
 
 var daemonCmd = &cobra.Command{
@@ -39,10 +40,11 @@ var daemonCmd = &cobra.Command{
 			addr = cfg.ListenAddr
 		}
 		srv := daemon.NewServer(daemon.Options{
-			DB:    db,
-			Log:   log,
-			Addr:  addr,
-			Actor: "daemon",
+			DB:        db,
+			Log:       log,
+			Addr:      addr,
+			Actor:     "daemon",
+			PprofAddr: pprofAddr,
 		})
 
 		// Wire the orca.v1.Dispatch service (v0.2 P02). The executor
@@ -71,6 +73,9 @@ var daemonCmd = &cobra.Command{
 		fmt.Fprintln(cmd.OutOrStdout(), "  /v1/tasks                       - list tasks")
 		fmt.Fprintln(cmd.OutOrStdout(), "  /orca.v1.Dispatch/Submit        - cross-node job submit (P02)")
 		fmt.Fprintln(cmd.OutOrStdout(), "  /orca.v1.Dispatch/Status        - cross-node job status (P02)")
+		if pprofAddr != "" {
+			fmt.Fprintf(cmd.OutOrStdout(), "  /debug/pprof/ (pprof)        - %s\n", pprofAddr)
+		}
 		fmt.Fprintln(cmd.OutOrStdout(), "  press Ctrl+C to stop")
 
 		ctx, stop := signal.NotifyContext(cmd.Context(), os.Interrupt, syscall.SIGTERM)
@@ -90,6 +95,7 @@ var daemonCmd = &cobra.Command{
 
 func init() {
 	daemonCmd.Flags().StringVar(&daemonAddr, "addr", ":8080", "listen address")
+	daemonCmd.Flags().StringVar(&pprofAddr, "pprof", "", "enable pprof endpoint on <addr> (e.g. :6060); unauthenticated, operator-only")
 	rootCmd.AddCommand(daemonCmd)
 	_ = slog.Default // keep import if unused above
 }

internal/cli/daemon_test.go

@@ -0,0 +1,13 @@
+package cli
+
+import "testing"
+
+func TestDaemonPprofFlag(t *testing.T) {
+	f := daemonCmd.Flags().Lookup("pprof")
+	if f == nil {
+		t.Fatal("--pprof flag not registered on daemonCmd")
+	}
+	if f.DefValue != "" {
+		t.Errorf("--pprof default = %q, want empty", f.DefValue)
+	}
+}