fix(jobs): drop --dataset.root on resume + restore keyboard-control docs

Address the latest Claude review on #3856:

- _build_resume_job no longer forwards --dataset.root to the pod (a
  host-local path it can't read); the fresh-run path already nulls it in
  build_remote_config_file, so this makes resume consistent. Add a unit
  test for _pod_forwarded_args covering the drop in both flag forms.
- Restore the display-independent keyboard-control docs (n/r/q letter
  equivalents + X11/Wayland/headless Tip) in il_robots.mdx that this
  branch was stale on relative to main (#3875).

src/lerobot/jobs/hf.py

@@ -256,7 +256,7 @@ def _build_resume_job(cfg: TrainPipelineConfig, username: str) -> tuple[str, lis
     config_path = parser.parse_arg("config_path")
     forwarded = _pod_forwarded_args(
         sys.argv[1:],
-        drop_names=("--config_path", "--policy.repo_id", "--policy.push_to_hub"),
+        drop_names=("--config_path", "--policy.repo_id", "--policy.push_to_hub", "--dataset.root"),
         drop_prefixes=("--job.",),
     )
 

tests/jobs/test_hf.py

@@ -23,6 +23,7 @@ import pytest
 
 from lerobot.configs.train import TrainPipelineConfig
 from lerobot.jobs.hf import (
+    _pod_forwarded_args,
     _poll_until_done,
     build_remote_config_file,
     build_repo_id,
@@ -123,6 +124,29 @@ def test_build_repo_id_sanitizes_and_timestamps():
     assert build_repo_id("alice", "///", now) == "alice/train_2026-06-19_10-22-03"
 
 
+def test_pod_forwarded_args_drops_host_only_flags():
+    """User overrides are replayed on the pod, minus flags that only make sense on the submitter.
+
+    `--dataset.root` is a host-local path the pod can't read, so it must be dropped in both the
+    `--name=value` and `--name value` forms; unrelated overrides are forwarded untouched.
+    """
+    argv = [
+        "--config_path=u/d",
+        "--dataset.root=/local/data",
+        "--dataset.root",
+        "/other/local/data",
+        "--policy.repo_id=u/keep",
+        "--steps=10",
+        "--job.target=a10g-small",
+    ]
+    forwarded = _pod_forwarded_args(
+        argv,
+        drop_names=("--config_path", "--policy.repo_id", "--policy.push_to_hub", "--dataset.root"),
+        drop_prefixes=("--job.",),
+    )
+    assert forwarded == ["--steps=10"]
+
+
 def _minimal_cfg():
     return draccus.parse(
         TrainPipelineConfig,