feat(sp7): claim detail includes lineReconciliation slim projection

backend/tests/test_api_claim_detail.py

@@ -211,4 +211,26 @@ def test_get_claim_detail_matched_remit_inlines_summary(seeded_store_with_pair):
     assert mr["status"] in {"received", "reconciled"}
     # ISO timestamp must end in Z — the spec contract that lets the
     # UI render the time without a tz suffix shim.
-    assert mr["receivedAt"].endswith("Z"), mr["receivedAt"]
+    assert mr["receivedAt"].endswith("Z"), mr["receivedAt"]
+
+
+def test_get_claim_detail_includes_line_reconciliation_slim_projection(seeded_store):
+    """SP7 §5.2: claim detail exposes a `lineReconciliation` slim list
+    parallel to `serviceLines`, indexed by line number. The values are
+    strings (Decimals serialized) or nulls when the line is unmatched."""
+    cid = seeded_store.get("/api/claims", headers=JSON).json()["items"][0]["id"]
+    resp = seeded_store.get(f"/api/claims/{cid}")
+    assert resp.status_code == 200, resp.text
+    body = resp.json()
+    assert "lineReconciliation" in body
+    lr_list = body["lineReconciliation"]
+    assert isinstance(lr_list, list)
+    # No 835 was ingested in this fixture, so every line is unmatched
+    # on the 835 side — the default for an unpaired claim.
+    for row in lr_list:
+        assert "lineNumber" in row
+        assert "status" in row
+        assert "paid" in row
+        assert "adjustmentsSum" in row
+    # One entry per service line.
+    assert len(lr_list) == len(body["serviceLines"])