feat: wire Infisical secret store into API server and MCP tools

- Wire secretsManager in NewHandler() — instantiate InfisicalBackend
  when OIKOS_INFISICAL_SITE_URL is set (previously always nil)
- Add get_secret, list_secrets, set_secret MCP tools with nil-backend
  graceful degradation
- Add oikos secret get|set|list CLI subcommands for Infisical
- Fix Set() bug: create-before-update so new keys are created;
  add Type: "shared" to Update so it finds the right secret;
  disable SDK cache so Get returns fresh data after Set
- Clean enrollment response: remove fake infisical_client_id/
  infisical_client_secret stubs, store age key in Infisical for real

cmd/oikos/main.go

@@ -115,7 +115,7 @@ Roles:
   scheduler  Run the observe loop
   notifier   Run the notification service (Matrix alerts)
   all        Run all roles in one process (dev mode)
-  secret     Secret management (Infisical)
+  secret     Secret management (Infisical: get, set, list, migrate, export-sops)
   knowledge  Convert wiki to knowledge seed (one-shot)
   version    Print version info
 
@@ -289,20 +289,45 @@ func runWithPool(ctx context.Context, cfg config.Config, name string, fn func(co
 
 func runSecret(ctx context.Context, cfg config.Config) {
 	if len(os.Args) < 3 {
-		fmt.Fprintln(os.Stderr, "usage: oikos secret <list|migrate|export-sops>")
+		fmt.Fprintln(os.Stderr, "usage: oikos secret <get|set|list|migrate|export-sops>")
 		os.Exit(1)
 	}
 
 	sub := os.Args[2]
-	secretsDir := cfg.SecretsDir
-	if secretsDir == "" {
-		secretsDir = "archive/secrets-sops-backup"
-	}
-	sopsBackend := secrets.NewSOPSBackend(secretsDir)
 
+	// For get/set/list: use Infisical directly
 	switch sub {
+	case "get":
+		if len(os.Args) < 4 {
+			fmt.Fprintln(os.Stderr, "usage: oikos secret get <key>")
+			os.Exit(1)
+		}
+		key := os.Args[3]
+		backend := newInfisicalBackendOrFail(cfg)
+		val, err := backend.Get(ctx, key)
+		if err != nil {
+			slog.Error("secret get", "key", key, "error", err)
+			os.Exit(1)
+		}
+		fmt.Println(val)
+
+	case "set":
+		if len(os.Args) < 5 {
+			fmt.Fprintln(os.Stderr, "usage: oikos secret set <key> <value>")
+			os.Exit(1)
+		}
+		key := os.Args[3]
+		value := os.Args[4]
+		backend := newInfisicalBackendOrFail(cfg)
+		if err := backend.Set(ctx, key, value); err != nil {
+			slog.Error("secret set", "key", key, "error", err)
+			os.Exit(1)
+		}
+		fmt.Printf("stored: %s\n", key)
+
 	case "list":
-		keys, err := sopsBackend.List(ctx)
+		backend := newInfisicalBackendOrFail(cfg)
+		keys, err := backend.List(ctx)
 		if err != nil {
 			slog.Error("secret list", "error", err)
 			os.Exit(1)
@@ -311,24 +336,46 @@ func runSecret(ctx context.Context, cfg config.Config) {
 			fmt.Println(k)
 		}
 
-	case "migrate":
-		infCfg := secrets.InfisicalConfig{
-			SiteURL:      cfg.InfisicalSiteURL,
-			ClientID:     cfg.InfisicalClientID,
-			ClientSecret: cfg.InfisicalClientSecret,
-			ProjectID:    cfg.InfisicalProjectID,
-			SecretPath:   "/",
-			Env:          cfg.InfisicalEnv,
-		}
-		if infCfg.Env == "" {
-			infCfg.Env = "dev"
-		}
-		if infCfg.SiteURL == "" {
-			fmt.Fprintln(os.Stderr, "error: OIKOS_INFISICAL_SITE_URL not set")
-			os.Exit(1)
-		}
+	case "migrate", "export-sops":
+		runSecretLegacy(ctx, cfg, sub)
 
-		infBackend := secrets.NewInfisicalBackend(infCfg)
+	default:
+		fmt.Fprintf(os.Stderr, "unknown secret command: %s\n", sub)
+		os.Exit(1)
+	}
+}
+
+// newInfisicalBackendOrFail creates an Infisical backend from config or exits.
+func newInfisicalBackendOrFail(cfg config.Config) *secrets.InfisicalBackend {
+	if cfg.InfisicalSiteURL == "" {
+		fmt.Fprintln(os.Stderr, "error: OIKOS_INFISICAL_SITE_URL not set")
+		os.Exit(1)
+	}
+	infCfg := secrets.InfisicalConfig{
+		SiteURL:      cfg.InfisicalSiteURL,
+		ClientID:     cfg.InfisicalClientID,
+		ClientSecret: cfg.InfisicalClientSecret,
+		ProjectID:    cfg.InfisicalProjectID,
+		SecretPath:   "/",
+		Env:          cfg.InfisicalEnv,
+	}
+	if infCfg.Env == "" {
+		infCfg.Env = "dev"
+	}
+	return secrets.NewInfisicalBackend(infCfg)
+}
+
+// runSecretLegacy handles SOPS-only commands (migrate, export-sops).
+func runSecretLegacy(ctx context.Context, cfg config.Config, sub string) {
+	secretsDir := cfg.SecretsDir
+	if secretsDir == "" {
+		secretsDir = "archive/secrets-sops-backup"
+	}
+	sopsBackend := secrets.NewSOPSBackend(secretsDir)
+
+	switch sub {
+	case "migrate":
+		infBackend := newInfisicalBackendOrFail(cfg)
 		keys, err := sopsBackend.List(ctx)
 		if err != nil {
 			slog.Error("migrate: read sops", "error", err)
@@ -366,10 +413,6 @@ func runSecret(ctx context.Context, cfg config.Config) {
 			fmt.Printf("%s: <sops-encrypted>\n", k)
 		}
 		fmt.Printf("\n# To restore: sops -d secrets/*.yaml\n")
-
-	default:
-		fmt.Fprintf(os.Stderr, "unknown secret command: %s\n", sub)
-		os.Exit(1)
 	}
 }