feat(map): add edge-center delta stats, thickness overlay, and layout fix

- Add edge-center sensor pair tables and delta calculations per wafer family.
- Parse and interpolate wafer thickness CSV data for offscreen visualization.
- Refactor ReadoutPanel layout using Item + anchors to fix right-margin clipping.
- Compact E-C Delta text format to fit standard sidebar width.
- Add pytest suite covering delta calculations, layout pairs, and thickness CSV.

tests/test_session_controller.py

@@ -248,3 +248,47 @@ def test_on_live_frame_emits_trend_delta_with_elapsed_seconds(controller, monkey
     elapsed, avg = payload[0]
     assert elapsed == pytest.approx(2.5)
     assert avg == pytest.approx(20.0)
+
+
+# ---- edge-center stats exposure (ADR-0002) ----
+
+def _write_f_family_csv(path):
+    """22-sensor F-family stream: pair (0,18) has delta 1.0, all others 0."""
+    n = 22
+    values = [149.0] * n
+    values[0] = 150.0
+    lines = [
+        "Wafer ID=F12",
+        "Acquisition Date=03/26/2025",
+        "Label," + ",".join(str(i + 1) for i in range(n)),
+        "X (mm)," + ",".join(str(i) for i in range(n)),
+        "Y (mm)," + ",".join(str(i) for i in range(n)),
+        "data",
+        "0.0," + ",".join(f"{v:.1f}" for v in values),
+    ]
+    path.write_text("\n".join(lines) + "\n", encoding="utf-8")
+
+
+def test_stats_include_edge_center_for_known_family(controller, tmp_path):
+    csv = tmp_path / "f_run.csv"
+    _write_f_family_csv(csv)
+    controller.loadFile(str(csv))
+    s = controller.stats
+    assert s["ecMaxDelta"] == pytest.approx(1.0)
+    assert s["ecMaxEdgeIndex"] == 1 and s["ecMaxCenterIndex"] == 19  # 1-origin
+    assert s["ecMaxEdgeValue"] == pytest.approx(150.0)
+    assert s["ecMaxCenterValue"] == pytest.approx(149.0)
+    assert s["ecMinDelta"] == pytest.approx(0.0)
+
+
+def test_stats_edge_center_skips_replaced_sensor(controller, tmp_path):
+    csv = tmp_path / "f_run.csv"
+    _write_f_family_csv(csv)
+    controller.loadFile(str(csv))
+    controller.replaceSensor(0, 149.0)  # replaced: pair (0,18) must be skipped
+    assert controller.stats["ecMaxDelta"] == pytest.approx(0.0)
+
+
+def test_stats_edge_center_absent_for_unknown_or_short_family(controller):
+    controller.loadFile("tests/fixtures/sample_stream.csv")  # A12, 3 sensors
+    assert "ecMaxDelta" not in controller.stats