test: add temporary Guacamole fixture access helper

docs/README.md

@@ -20,6 +20,8 @@ Read the documents in this order:
 8. [Provisioned Windows test VM](testing-vm.md) — exact fixture identity,
    host/guest access, endpoints, snapshots, credentials contract, reset
    procedure, and known limitations.
+9. [Interactive VM access](../test/rdp-access/README.md) — temporary,
+   self-signed HTTPS browser gateway for the rare manual UAC recovery step.
 
 The wire authority is in [`../protos/rvbox/v1`](../protos/rvbox/v1):
 `common.proto` contains shared data types, `agent.proto` contains the

docs/implementation-plan.v1.md

@@ -847,6 +847,14 @@ The normal active `rvboxtest` session remains the target for execution-role
 tests. The consent-prompt branch itself remains an interactive UAC test; an
 invisible Guest Control session must never answer it.
 
+When that bounded manual step is necessary, use the tracked Docker-only
+[`test/rdp-access`](../test/rdp-access/README.md) helper. It starts a
+self-signed HTTPS Guacamole gateway only after `test-host prepare` holds the
+fixture lease; VRDE remains loopback-only on Helium and its SSH tunnel is bound
+only to the helper's private Docker gateway. Stop the helper before the normal
+`test-host reset`. It is a recovery interface, not a product component or a
+replacement for Guest Control/native test automation.
+
 For this provisioned lane, the approved host-only credential-file location is
 `/home/cabbage/.local/share/rvbox-secrets/rvbox-win10-test.password`. It must
 remain mode `0600`, is never read into a repository process, and is supplied to

docs/testing-vm.md

@@ -85,6 +85,12 @@ VirtualBox 7.2.16 does not handle reliably, and earlier probes included
 headless-server crashes. Use Guest Control for deterministic setup, execution,
 and collection. Do not expose the VM's RDP endpoints beyond the test LAN.
 
+For the rare interactive UAC/manual-recovery step, use the Docker-only helper
+in [`test/rdp-access`](../test/rdp-access/README.md). It creates a temporary
+self-signed HTTPS Guacamole gateway while retaining VRDE on Helium loopback and
+the SSH tunnel on a private Docker gateway. Follow its full lease/prepare/up/
+down/reset lifecycle; it is not an alternative to the native test controller.
+
 ## Snapshots and reset contract
 
 Three clean snapshots exist and must be retained. `baseline-clean-administrator`

docs/testing.md

@@ -138,6 +138,11 @@ than treating it as a stable endpoint. VRDE is enabled only on Helium loopback
 at `127.0.0.1:3389` for diagnostics, while native Windows RDP is disabled in
 the baseline.
 
+Interactive browser access is a deliberately temporary recovery path only. See
+[`test/rdp-access`](../test/rdp-access/README.md) for the Docker-only,
+self-signed HTTPS Guacamole lifecycle; it must be started only after the native
+fixture controller has prepared and leased the VM, and stopped before reset.
+
 The canonical headless VirtualBox/Guest Control adapter is
 `scripts/windows/test-host`. It is a POSIX controller script because the
 fixture's VirtualBox host is Arch Linux and has no PowerShell runtime. The