docs(cloudxr): document the client timeout env vars and test that 0 passes through

docs/source/references/oob_teleop_control.rst

@@ -609,6 +609,21 @@ Environment variables
      - Non-negative delay between browser-local attempts in milliseconds
        (default ``3000``). The host derives its bounded recovery grace from
        this value and the maximum-attempt count.
+   * - ``TELEOP_CLIENT_STREAM_ATTACH_TIMEOUT_MS``
+     - Base timeout in milliseconds for the web client to detect a stream that
+       never attaches (client default ``120000``; doubles per retry). ``0``
+       disables this detection. Included in the generated headset URL.
+   * - ``TELEOP_CLIENT_WARMUP_BEGIN_TIMEOUT_MS``
+     - Timeout in milliseconds for the web client to see the first decoder
+       warm-up signal after the stream attaches (client default ``10000``).
+       ``0`` disables this detection. Included in the generated headset URL.
+   * - ``TELEOP_CLIENT_WARMUP_END_TIMEOUT_MS``
+     - Timeout in milliseconds for decoder warm-up to finish once it has begun
+       (client default ``30000``). ``0`` disables all warm-up detection,
+       including the begin timeout. Set this to ``0`` when the OpenXR
+       application starts after the headset connects: until it submits frames
+       the server sends only idle frames, which the client cannot tell apart
+       from a stuck warm-up. Included in the generated headset URL.
    * - ``USB_BACKEND_PORT``
      - CloudXR backend port the headset reaches via ``adb reverse`` in
        ``--usb-local`` mode (default ``49100``).

tests/python/core/cloudxr/test_oob_teleop_env.py

@@ -405,6 +405,20 @@ def test_client_ui_fields_from_env_invalid_timeout_ignored(
     assert "streamAttachTimeoutMs" not in fields
 
 
+def test_zero_warmup_timeout_env_reaches_bookmark_url(
+    clear_teleop_env: None, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """0 means "disabled" to the web client, so it must survive as a field and a query param."""
+    monkeypatch.setenv("TELEOP_CLIENT_WARMUP_END_TIMEOUT_MS", "0")
+    fields = client_ui_fields_from_env()
+    assert fields["warmupEndTimeoutMs"] == 0
+    u = build_headset_bookmark_url(
+        web_client_base="https://h.test/",
+        stream_config={"serverIP": "10.0.0.1", "port": 48322, **fields},
+    )
+    assert parse_qs(urlparse(u).query)["warmupEndTimeoutMs"] == ["0"]
+
+
 def test_build_headset_bookmark_url_reconnect_enabled() -> None:
     """reconnectEnabled=True from stream_config is serialised as "true" in the bookmark URL."""
     u = build_headset_bookmark_url(