feat(clients): CLI-04 typed single-item command parity (+CLI-30 unregister) — 4/5 clients

Every parity-critical single-item MXAccess command now has a typed session
helper instead of only a raw-Invoke escape hatch. Added per client:
- Phase 1: AdviseSupervisory, WriteSecured, WriteSecured2, AuthenticateUser,
  ArchestrAUserToId
- Phase 2: AddBufferedItem, SetBufferedUpdateInterval, Suspend, Activate
- CLI-30: Unregister (Rust + .NET; Go/Python already had it)

Each wraps the existing raw-command machinery (no new wire surface) and runs the
same MXAccess-level reply validation (hresult < 0 + MxStatusProxy). MXAccess
parity preserved: WriteSecured before AuthenticateUser+AdviseSupervisory surfaces
the native failure unchanged (not pre-validated/reordered). Credentials
(AuthenticateUser password, WriteSecured payloads) route through each client's
secret-redaction seam and never reach logs/exceptions/ToString/Debug/Display;
each suite asserts a distinctive credential is absent from surfaced errors. New
CLI subcommands source credentials via flag/env, never echoed.

- .NET: 21 helpers (validated + Raw), CLI subcommands, multi-secret CLI redactor.
  Build clean (0 warn), 102 passed.
- Go: 9 helpers + *Raw variants, redactSecrets seam, promoted CLI advise-supervisory
  to typed. gofmt/vet/build/test clean.
- Rust: 10 helpers incl. unregister; verified ensure_mxaccess_success runs on
  secured paths; error.rs credential scrub. fmt/check/test/clippy clean.
- Python: 9 async helpers, redact_secret seam + _invoke_redacted, CLI commands.
  145 passed.
- Shared doc: ClientLibrariesDesign "Typed Command Parity" section.

Java client typed parity is batched to windev (no local JRE); CLI-04 + CLI-30
stay open until it lands.

Claude-Session: https://claude.ai/code/session_01DMXXvNuPekkkrTEyPNxEkW

clients/go/cmd/mxgw-go/main_test.go

@@ -568,6 +568,36 @@ func TestRunAdviseSupervisoryRequiresSessionID(t *testing.T) {
 	}
 }
 
+// TestRunWriteSecuredRequiresSessionID pins the write-secured session-id guard so
+// it fails fast before dialing.
+func TestRunWriteSecuredRequiresSessionID(t *testing.T) {
+	var stdout, stderr bytes.Buffer
+	err := runWithIO(t.Context(), []string{"write-secured", "-plaintext", "-api-key", "test"}, &stdout, &stderr)
+	if err == nil || !strings.Contains(err.Error(), "session-id is required") {
+		t.Fatalf("write-secured without -session-id error = %v", err)
+	}
+}
+
+// TestRunAuthenticateUserRequiresVerifyUser pins that authenticate-user fails fast
+// (before dialing) when the user is absent, and never echoes any credential in
+// the guard error.
+func TestRunAuthenticateUserRequiresVerifyUser(t *testing.T) {
+	var stdout, stderr bytes.Buffer
+	err := runWithIO(t.Context(), []string{
+		"authenticate-user",
+		"-session-id", "s1",
+		"-password", "hunter2-password",
+		"-plaintext",
+		"-api-key", "test",
+	}, &stdout, &stderr)
+	if err == nil || !strings.Contains(err.Error(), "verify-user is required") {
+		t.Fatalf("authenticate-user without -verify-user error = %v", err)
+	}
+	if strings.Contains(err.Error(), "hunter2-password") {
+		t.Fatalf("authenticate-user guard error leaked the credential: %v", err)
+	}
+}
+
 // TestRunWriteBulkVariantRejectsMismatchedHandlesAndValues pins the len-mismatch
 // guard so a write-bulk with unequal item-handles / values counts fails fast
 // before any dial.