fix(docs): sim teleop fence passes robot_name to teleoperate only

[shipitfast]

What

The "Teleoperate a simulation (MuJoCo)" fence in docs/hardware/teleoperation.md now passes robot_name only to teleoperate(), where it is read.

Why

attach_teleop forwards every kwarg it does not read to Teleoperator(), whose config filter refuses the fence's robot_name="arm0" before any device is touched, so every reader of that fence hit ValueError: Unknown kwarg(s) for teleop_type='so101_leader': ['robot_name']. The new grader on main:

AssertionError: docs/hardware/teleoperation.md: attach_teleop('so101_leader', ...) passes ['robot_name'], which neither attach_teleop reads nor Teleoperator('so101_leader') accepts

Tests

tests/test_docs_attach_teleop_kwargs_reach_the_config.py resolves each documented attach_teleop("<type>", ...) kwarg against the mixin's keyword-only args and the lerobot config dataclass the factory consults. ruff, mypy clean on touched files.

[cagataycali]

The docs fix is right and the premise holds in source: _build_teleop_config computes recognised = set(forwardable) | {"id"} | valid_fields and refuses anything outside it, which is exactly the oracle the grader rebuilds, and robot_name is in neither half. The fence on main therefore raises before any device is touched, as described.

One must-fix in the new test and one nit, both in the same file, so one commit and a plain push covers both. Changelog graders (91) and the tests/-scanning tree graders (136) pass on this head; the fork's CI runs were held at action_required and have been released.

[cagataycali]

Both threads addressed on b2d7506; main absorbed (was 54 behind). The gate string is lerobot.teleoperators.config, the narrowest module this grader reads, and the import is now plain top-level like the 102 siblings that reach lerobot.

grader	lerobot absent	lerobot installed
c5ab6a5	13 failed, 1 passed	14 passed
b2d7506	1 skipped	14 passed

Still non-vacuous: against the pre-fix fence it is 1 failed, 13 passed, and the one failure names the kwarg. The fence's premise reproduces on a live MuJoCo sim -- attach_teleop("so101_leader", ..., robot_name="arm0") raises ValueError: Unknown kwarg(s) ... ['robot_name'] before any device is touched, and robot_name is a teleoperate() parameter.

Gate: ruff + mypy clean (1,999 files), 19 whole-tree graders + changelog 994 passed, -k "docs or teleop" 2,268 passed / 6 skipped, mkdocs --strict clean, no overlap with main.

[cagataycali]

Green on b2d7506c: rollup SUCCESS, MERGEABLE, both review threads resolved, one approval recorded. reviewDecision is still REVIEW_REQUIRED, so a second approving account is the only gate left. @yinsong1986 over to you.

[yinsong1986]

Summary

One-line docs fix plus a grader that keeps it fixed. The "Teleoperate a simulation (MuJoCo)" fence in docs/hardware/teleoperation.md passed robot_name="arm0" to attach_teleop, which forwards every kwarg it does not read (name/method/map_fn) to the Teleoperator() factory, whose _build_teleop_config rejects unknown kwargs with a ValueError before any device is touched — so the fence failed for every reader. The fence now passes robot_name only to teleoperate(), where it is actually read. The new test resolves every documented attach_teleop("<type>", ...) keyword against the mixin's own keyword-only args plus the lerobot config dataclass the factory consults, so the same class of doc rot fails CI instead of readers. Verified against head: the mixin/factory contracts the test encodes match strands_robots/teleop_mixin.py and strands_robots/teleoperator.py on b2d7506c.

What's good

• Both prior review threads are resolved on this head: the module gates on pytest.importorskip("lerobot.teleoperators.config") (lerobot is an extra, not a base dep) and the mixin-source read now pins encoding="utf-8".
• The grader includes a vacuity guard (test_the_docs_still_attach_a_teleoperator_by_type) so an empty case list cannot pass silently.
• The oracle is lerobot's own registry (TeleoperatorConfig.get_choice_class), not a hand-maintained copy, so it tracks upstream config changes for free.
• Tight scope: docs line, changelog fragment, one test module.