feat(perception): expire costmap permissions per cell

tests/test_perception_realtime_scene.py

@@ -8,6 +8,7 @@ from pathlib import Path
 
 import pytest
 
+from k1link.perception.costmap_freshness import CostmapCellEvidence
 from k1link.perception.realtime_contract import (
     REQUIRED_LAYERS,
     LayerEvidence,
@@ -296,3 +297,112 @@ def test_pilot_rejects_wrong_run_sequence_and_control_authority(pilot):
     changed["commands_enabled"] = True
     with pytest.raises(ValueError, match="authority"):
         pilot.validate_receipt(changed, bundle, epoch_id="pilot")
+
+
+@pytest.mark.parametrize("own_time", [NOW + 1, True])
+def test_derivation_cannot_hide_invalid_own_time_behind_an_older_parent(own_time):
+    value = scene(held_ms=100)
+    with pytest.raises(RealtimeContractError):
+        derive_layer(
+            "costmap",
+            epoch_id="epoch",
+            source_sequence=2,
+            source_time_ns=NOW,
+            payload_sha256="a" * 64,
+            inputs=tuple(value.layers[i] for i in (0, 2, 3)),
+            oldest_required_input_time_ns=own_time,
+        )
+
+
+def cell_input():
+    payload, bundle, ddr = pilot_input()
+    payload["costmap_states"] = [1, 1]
+    payload["costmap_material"] = [1, 1]
+    payload["policy_actions"] = [0, 0]
+    payload["policy_counts"] = {"ALLOW_candidate": 2, "HIGH_COST": 0, "NO_GO": 0}
+    payload["costmap_cell_evidence"] = CostmapCellEvidence((NOW - 200_000_000, NOW)).to_dict()
+    payload["tgs_counts"]["oldest_permissive_cell_source_ns"] = NOW - 200_000_000
+    return payload, bundle, ddr
+
+
+def test_consumer_expires_only_old_cell_and_rehashes_view_without_mutating_wire(pilot):
+    payload, bundle, ddr = cell_input()
+    pilot.prepare_publication(
+        payload,
+        bundle,
+        ddr,
+        epoch_id="pilot",
+        now_ns=bundle["due_ns"] + 10_000_000,
+        mode="per-cell",
+    )
+    original = copy.deepcopy(payload)
+    freshness = pilot.validate_receipt(payload, bundle, epoch_id="pilot")
+    view, checked = pilot.assess_receipt(
+        payload,
+        freshness,
+        bundle=bundle,
+        now_ns=bundle["due_ns"] + 60_000_000,
+    )
+    assert checked.fresh_complete
+    assert view["costmap_states"] == [3, 1] and view["policy_actions"] == [2, 0]
+    assert view["cell_assessment"]["expired_ground_cells"] == 1
+    assert checked.layers[4].oldest_required_input_time_ns == NOW - 20_000_000
+    assert payload == original
+    derived = pilot.validate_receipt(view, bundle, epoch_id="pilot")
+    assert derived.source_time_ns == freshness.source_time_ns
+    aged, expired = pilot.assess_receipt(
+        view,
+        derived,
+        bundle=bundle,
+        now_ns=bundle["due_ns"] + 260_000_000,
+    )
+    assert not expired.fresh_complete and aged["policy_actions"] == [2, 2]
+    pilot.validate_receipt(aged, bundle, epoch_id="pilot")
+    with pytest.raises(ValueError, match="backwards"):
+        pilot.assess_receipt(view, derived, bundle=bundle, now_ns=bundle["due_ns"])
+
+
+@pytest.mark.parametrize("missing,held_ms", [(True, 0), (False, 220)])
+def test_cell_freshness_cannot_override_missing_lidar_or_stale_segmentation(
+    pilot, missing, held_ms
+):
+    payload, bundle, ddr = cell_input()
+    bundle["available"] = not missing
+    if held_ms:
+        ddr.update(state="held", source_sequence=1, source_host_monotonic_ns=NOW - 220_000_000)
+    pilot.prepare_publication(
+        payload,
+        bundle,
+        ddr,
+        epoch_id="pilot",
+        now_ns=bundle["due_ns"],
+        mode="per-cell",
+    )
+    fresh = pilot.validate_receipt(payload, bundle, epoch_id="pilot")
+    view, checked = pilot.assess_receipt(
+        payload,
+        fresh,
+        bundle=bundle,
+        now_ns=bundle["due_ns"] + 60_000_000,
+    )
+    assert not checked.fresh_complete and view["policy_actions"] == [2, 2]
+    pilot.validate_receipt(view, bundle, epoch_id="pilot")
+
+
+def test_cell_timestamp_and_mode_are_bound_to_costmap_hash(pilot):
+    payload, bundle, ddr = cell_input()
+    pilot.prepare_publication(
+        payload,
+        bundle,
+        ddr,
+        epoch_id="pilot",
+        now_ns=bundle["due_ns"],
+        mode="per-cell",
+    )
+    changed = copy.deepcopy(payload)
+    changed["costmap_cell_evidence"]["observed_source_time_ns"][0] = str(NOW)
+    with pytest.raises(ValueError, match="digest"):
+        pilot.validate_receipt(changed, bundle, epoch_id="pilot")
+    payload["costmap_freshness_mode"] = "whole-scene"
+    with pytest.raises(ValueError, match="digest"):
+        pilot.validate_receipt(payload, bundle, epoch_id="pilot")