[AZ-408] [AZ-410] [AZ-411] Batch 69: synth injectors + FT-P-02/03/14

AZ-408 (3pt) — Replace AZ-406 injector scaffolds with concrete generators:
- outlier.py: deterministic stride + far-away tile replacement; AC-2 ≥350m offset
- blackout_spoof.py: paired video blackout + FC GPS spoof with ≤40ms alignment;
  AC-4 realistic fix_type/hdop; AC-NEW-8 200-500m inter-spoof deltas
- multi_segment.py: ≥3 disjoint windows, ≥30s gaps, ≤25% coverage
- fc_proxy.py: timed-splice runtime proxy with pre-activate RuntimeError guard
- _common.py: derive_rng + tile-manifest reader + tmpfs helpers
- injector_fixtures.py: pytest fixtures wired via runner conftest

AZ-410 (3pt) — FT-P-02 cumulative drift between satellite anchors:
- anchor_pair_detector.py: AC-1 detection, AC-2/3 pass-fraction,
  AC-4 monotonicity check, CSV evidence
- test_ft_p_02_derkachi_drift.py: scenario gated on upstream helper
  NotImplementedError (frame_source_replay / fdr_reader / imu_replay)

AZ-411 (2pt) — FT-P-03 + FT-P-14 schema + WGS84:
- estimate_schema.py: AC-1 schema completeness, AC-2 source-label set
  containment, AC-3 WGS84 range + int32 1e-7 decode
- test_ft_p_03_14_schema_wgs84.py: shared single-image-push scenario

Tests: 248 unit tests pass (+91 vs batch 68).
Reports: batch_69_report.md, batch_69_review.md (PASS),
cumulative_review_batches_67-69_cycle1_report.md (PASS).

Co-authored-by: Cursor <cursoragent@cursor.com>

e2e/_unit_tests/fixtures/test_multi_segment.py

@@ -0,0 +1,172 @@
+"""Behavioural tests for the AZ-408 multi_segment injector.
+
+Covers AC-5 (≥3 disjoint windows, ≥30 s gaps, ≤25 % total coverage) and
+AC-6 (tmpfs scratch isolation).
+"""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+import pytest
+
+from fixtures.injectors import multi_segment
+
+
+def _build_synthetic_frames_dir(parent: Path, count: int) -> Path:
+    from PIL import Image  # noqa: PLC0415
+
+    frames_dir = parent / "frames"
+    frames_dir.mkdir(parents=True, exist_ok=True)
+    img = Image.new("RGB", (256, 256), color=(60, 60, 60))
+    for i in range(count):
+        img.save(
+            frames_dir / f"AD{i + 1:06d}.jpg",
+            format="JPEG", quality=85, optimize=False, progressive=False, subsampling=2,
+        )
+    return frames_dir
+
+
+def test_produces_three_disjoint_segments(tmp_path: Path) -> None:
+    """AC-5: 3 disjoint blackout windows."""
+    # Arrange
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=9000)  # 5 min @ 30 fps
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=3, segment_seconds=15.0
+    )
+
+    # Act
+    report = multi_segment.build(plan, tmp_path / "out")
+
+    # Assert
+    assert len(report.segments) == 3
+    # Each segment is non-empty
+    for s in report.segments:
+        assert s.end_ms > s.start_ms
+    # Disjoint
+    for prev, nxt in zip(report.segments, report.segments[1:]):
+        assert prev.end_ms < nxt.start_ms
+
+
+def test_segments_are_at_least_30_seconds_apart(tmp_path: Path) -> None:
+    """AC-5: consecutive segments separated by ≥30 s of normal frames."""
+    # Arrange
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=9000)
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=3, segment_seconds=12.0
+    )
+
+    # Act
+    report = multi_segment.build(plan, tmp_path / "out")
+
+    # Assert
+    for prev, nxt in zip(report.segments, report.segments[1:]):
+        gap_ms = nxt.start_ms - prev.end_ms
+        assert gap_ms >= 30_000, f"gap {gap_ms} ms < 30 s between segments"
+
+
+def test_total_blackout_below_25_percent(tmp_path: Path) -> None:
+    """AC-5: total blackout coverage ≤ 25 %."""
+    # Arrange
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=9000)
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=3, segment_seconds=15.0
+    )
+
+    # Act
+    report = multi_segment.build(plan, tmp_path / "out")
+
+    # Assert
+    assert report.total_blackout_fraction <= 0.25
+
+
+def test_rejects_overlapping_gap(tmp_path: Path) -> None:
+    """Infeasible plan: too many segments inside too short a source."""
+    # Arrange — 30 s source can't fit 3×12 s segments with 30 s gaps
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=900)
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=3, segment_seconds=12.0
+    )
+    # Act / Assert
+    with pytest.raises(ValueError, match="gap between segment|blackout fraction"):
+        multi_segment.build(plan, tmp_path / "out")
+
+
+def test_rejects_too_few_segments(tmp_path: Path) -> None:
+    """AC-5: n_segments must be ≥3."""
+    # Arrange
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=900)
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=2, segment_seconds=5.0
+    )
+    # Act / Assert
+    with pytest.raises(ValueError, match="n_segments must be ≥3"):
+        multi_segment.build(plan, tmp_path / "out")
+
+
+def test_rejects_zero_segment_seconds(tmp_path: Path) -> None:
+    # Arrange
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=900)
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=3, segment_seconds=0.0
+    )
+    # Act / Assert
+    with pytest.raises(ValueError, match="segment_seconds"):
+        multi_segment.build(plan, tmp_path / "out")
+
+
+def test_blackout_frames_are_black(tmp_path: Path) -> None:
+    """Frames inside any segment are all-zero (black) on disk."""
+    # Arrange
+    from PIL import Image  # noqa: PLC0415
+
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=9000)
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=3, segment_seconds=10.0
+    )
+    out_root = tmp_path / "out"
+    report = multi_segment.build(plan, out_root)
+
+    # Act
+    for seg in report.segments[:1]:  # spot-check first segment
+        for idx in range(seg.first_frame_idx, min(seg.first_frame_idx + 5, seg.last_frame_idx)):
+            name = f"AD{idx + 1:06d}.jpg"
+            img = Image.open(out_root / "frames" / name).convert("RGB")
+            r, g, b = img.getpixel((128, 128))  # type: ignore[misc]
+            # Assert
+            assert r < 5 and g < 5 and b < 5
+
+
+def test_summary_json_present_with_expected_fields(tmp_path: Path) -> None:
+    # Arrange
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=9000)
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=3, segment_seconds=10.0
+    )
+
+    # Act
+    multi_segment.build(plan, tmp_path / "out")
+    payload = json.loads((tmp_path / "out" / "summary.json").read_text())
+
+    # Assert
+    assert payload["scenario"] == "multi-segment-derkachi"
+    assert payload["n_segments"] == 3
+    assert payload["total_blackout_fraction"] <= 0.25
+
+
+def test_overwrites_existing_out_root(tmp_path: Path) -> None:
+    # Arrange
+    frames = _build_synthetic_frames_dir(tmp_path / "src", count=9000)
+    plan = multi_segment.MultiSegmentPlan(
+        source_frames_dir=frames, n_segments=3, segment_seconds=10.0
+    )
+    out_root = tmp_path / "out"
+    multi_segment.build(plan, out_root)
+    (out_root / "stale.txt").write_text("stale")
+
+    # Act
+    multi_segment.build(plan, out_root)
+
+    # Assert
+    assert not (out_root / "stale.txt").exists()