feat: order/delay in service files, enable cmd, --all on unit commands

- install/uninstall/start/stop/enable take <name> or --all; *all kept as shortcuts
- add enable (enable at boot + start); startall no longer enables
- order/delay resolved by config.ResolveOrder and written into systemd,
  OpenRC and runit service files (After=/sleep), so they apply at boot
- install --all stops and disables units before removing their files
- update regenerates all installed, enabled units and removes disabled ones
- edit creates the config dir; docs and man page updated
- tests: fake Init for cmd, ResolveOrder, backend ordering output

runit/runit_test.go

@@ -293,3 +293,32 @@ func TestParseStatus(t *testing.T) {
 		}
 	}
 }
+
+func TestGenerate_OrderAndDelay(t *testing.T) {
+	b, _ := setup(t)
+	u := config.Unit{Name: "web", Runtime: "podman", Enabled: true, After: []string{"db"}, StartDelay: 3 * time.Second}
+	got, err := b.Generate(u, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	link := filepath.Join(b.ServiceDir, "unitdore-db")
+	wait := "sv -w 30 check " + link + " >/dev/null 2>&1 || true\nsleep 3\n"
+	if !strings.Contains(got, wait) {
+		t.Errorf("missing %q in:\n%s", wait, got)
+	}
+	// waiting happens before the service command runs
+	if strings.Index(got, "sleep 3") > strings.Index(got, "exec /usr/bin/podman") {
+		t.Errorf("delay must precede exec:\n%s", got)
+	}
+}
+
+func TestGenerate_NoOrderNoExtras(t *testing.T) {
+	b, _ := setup(t)
+	got, err := b.Generate(config.Unit{Name: "a", Runtime: "podman", Enabled: true}, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if strings.Contains(got, "sv -w") || strings.Contains(got, "sleep") {
+		t.Errorf("unexpected ordering output:\n%s", got)
+	}
+}