fix(perception): bound vegetation load decoding

tests/test_lab_v1_vegetation_integrated_shadow.py

@@ -236,6 +236,9 @@ def test_worker_gate_reuses_shared_barrier_and_keeps_canonical_triton_unchanged(
     wrapper = POWERSHELL_PATH.read_text(encoding="utf-8")
     assert '"source-paced-integrated-shadow/v1"' in runner
     assert "wait_for_shared_start(" in runner
+    assert '"bounded-sequential-h264/v1"' in runner
+    assert '"full_route_rgb_prefetch": False' in runner
+    assert "decode_source(source_capture, expected_size)" in runner
     assert '"camera_semantics_can_clear_rigid_geometry": False' in runner
     assert "$VegetationLoadGate" in wrapper
     assert '"vegetation"' in wrapper