fix(docker): tee supervised gateway stdout to docker logs

Follow-up to #33583 (the gateway-run-supervised redirect).

Before this fix, the supervised gateway's stdout (most visibly the
"Hermes Gateway Starting…" rich-console banner) was swallowed by
`s6-log` into the rotated file at
`${HERMES_HOME}/logs/gateways/<profile>/current` and never reached
`docker logs`. Operational signal lived in two places:

  * **docker logs** — saw stderr (Python `logging` defaults to
    stderr), so warnings/errors were visible.
  * **the rotated file** — saw stdout (rich banners, `print()`
    output, third-party libs that wrote to fd 1).

This was surprising for users coming from the pre-s6 image, where
`docker run … gateway run` produced a single unified stream in
`docker logs`. They'd see partial output, conclude something was
broken, and dig around for the missing pieces.

Fix: add the `1` s6-log action directive before the file destination
so each line is forwarded to s6-log's stdout — which propagates up
the s6-supervise pipeline to /init's stdout = container stdout =
`docker logs`. The file destination is preserved as a second
destination, so the rotated log (with ISO 8601 timestamps) still
exists for `hermes logs` and for survival across container restarts.

Trade-off considered: timestamps. Putting `T` between `1` and the
file destination (not before `1`) means:

  * docker logs sees raw lines — Python's logging formatter has its
    own timestamps, and `docker logs --timestamps` adds another
    layer when desired. No double-stamping in the common reading
    path.
  * The persisted file gets s6-log's ISO 8601 timestamp so even
    output that lacked a Python-logger timestamp (rich banners,
    third-party raw prints) is correlatable in `current`.

Verification:

  * New unit-test assertion in `test_service_manager.py` locks the
    `s6-log 1` directive into the rendered run-script. Mutation-
    tested by reverting to the pre-fix script (no `1`); the assert
    catches it cleanly.
  * New docker-harness test `test_supervised_gateway_stdout_reaches_docker_logs`
    builds the image, runs `docker run … gateway run`, and asserts
    the unique `⚕` banner glyph reaches `docker logs`. Also verifies
    the rotated file still contains the banner (no regression on
    the existing file destination). Mutation-tested end-to-end: built
    a deliberately-broken image without the `1` directive and the
    test failed exactly as designed, citing the banner present in
    `current` but absent from `docker logs`.
  * `website/docs/user-guide/docker.md` gains a new `:::note Where
    gateway logs go` admonition documenting both destinations and
    the audit-log file at `${HERMES_HOME}/logs/container-boot.log`.

Existing functionality preserved: every other docker-harness test
still passes against the new image. Unit-test sweep across
`tests/hermes_cli/` (5561 tests) is green.

tests/hermes_cli/test_service_manager.py

@@ -555,6 +555,16 @@ def test_s6_register_creates_service_dir_and_triggers_scan(
     assert "/opt/data/logs/gateways/coder" not in log_text, (
         "log_dir was hard-coded; must use ${HERMES_HOME} at run time"
     )
+    # `1` action directive forwards lines to stdout BEFORE the file
+    # destination so the supervised gateway's stdout (including the
+    # rich-console banner and plain print() output) reaches docker
+    # logs, not just the rotated file. See _render_log_run's docstring
+    # for the full output-routing rationale.
+    assert "s6-log 1 " in log_text, (
+        "log/run must include the `1` action directive before the file "
+        "destination so supervised stdout reaches docker logs. Saw: "
+        f"{log_text!r}"
+    )
 
     # s6-svscanctl -a was invoked against the scandir
     assert any(