0.2.25: batch historical eNAV backfill + collapsible investor chart

Add POST /api/import/capital-accounts/batch: upload several of a fund's
eNAV workbooks at once; each file's ALLOC SI roster is auto-matched to
existing members (by fund-admin investor ID, else name/username) and their
capital statement is saved at that file's own as-of date, building
trend-lines without replacing the latest figures. Members not already in
the portal are skipped and reported per file (never created). Capital
statements only -- holdings/NAV are untouched. One bad file (wrong
password, no ALLOC SI, unreadable date) is reported per-file and does not
abort the rest.

Import page gains a "Backfill historical capital" batch section (fund
picker, multi-file .xlsx input, shared password, per-file results table).

Investor portal "Capital over time" chart is now collapsed by default and
expands per fund (first login opens clean); applies to InvestorHome and
the admin Investor View via the shared component.

Tests: backend/tests/test_capital_batch.py (2). Full suite 17 passed;
frontend tsc clean.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/tests/test_capital_batch.py

@@ -0,0 +1,107 @@
+"""Batch historical capital backfill: several eNAV files → per-quarter statements, auto-matched."""
+
+import io
+from datetime import date, datetime
+
+import openpyxl
+from sqlmodel import select
+
+from ten31portal.models import CapitalAccountStatement, Entity, EntityType, User, UserRole
+from tests.conftest import make_user
+
+
+def _alloc_si_file(report: datetime, rows: list[dict]) -> bytes:
+    """Build a minimal eNAV workbook with an ALLOC SI roster and a report date in A1."""
+    wb = openpyxl.Workbook()
+    ws = wb.active
+    ws.title = "ALLOC SI"
+    ws["A1"] = report  # _enav_as_of reads the report date from the top-left cells
+    header = ["INVESTOR ID", "INVESTOR TYPE", "INVESTOR NAME",
+              "COMMITTED CAPITAL", "CONTRIBUTIONS", "(DISTRIBUTIONS)", "ENDING BALANCE"]
+    ws.append([None] * 7)  # row 2 spacer
+    ws.append(header)      # row 3 header
+    for r in rows:
+        ws.append([
+            r.get("id"), "LP", r["name"],
+            r.get("commit", 0), r.get("contrib", 0), r.get("distrib", 0), r["ending"],
+        ])
+    out = io.BytesIO()
+    wb.save(out)
+    return out.getvalue()
+
+
+def test_batch_backfill_builds_history(auth_client, session):
+    fund = Entity(name="LTPF III", type=EntityType.fund)
+    session.add(fund)
+    session.commit()
+    session.refresh(fund)
+
+    # One member matched by fund-admin ID, one by name; both already exist.
+    alice = make_user(session, username="alice", name="Alice Trust",
+                      role=UserRole.investor, external_investor_id="INV-100")
+    make_user(session, username="bob", name="Bob Llc", role=UserRole.investor)
+
+    q3 = _alloc_si_file(datetime(2025, 9, 30), [
+        {"id": "INV-100", "name": "Alice Trust", "commit": 1_000_000, "contrib": 400_000, "ending": 420_000},
+        {"id": "INV-200", "name": "Bob LLC", "commit": 500_000, "contrib": 200_000, "ending": 205_000},
+        {"id": "INV-999", "name": "Ghost Capital", "commit": 999, "contrib": 999, "ending": 999},  # no account → skipped
+    ])
+    q4 = _alloc_si_file(datetime(2025, 12, 31), [
+        {"id": "INV-100", "name": "Alice Trust", "commit": 1_000_000, "contrib": 400_000, "ending": 455_000},
+        {"id": "INV-200", "name": "Bob LLC", "commit": 500_000, "contrib": 200_000, "ending": 210_000},
+    ])
+
+    resp = auth_client.post(
+        "/api/import/capital-accounts/batch",
+        data={"entity_id": fund.id},
+        files=[
+            ("files", ("LTPF_III_Q3.xlsx", q3, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet")),
+            ("files", ("LTPF_III_Q4.xlsx", q4, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet")),
+        ],
+    )
+    assert resp.status_code == 200, resp.text
+    body = resp.json()
+
+    assert body["total_statements"] == 4  # 2 members × 2 quarters
+    q3res = next(f for f in body["files"] if "Q3" in f["filename"])
+    assert q3res["as_of_date"] == "2025-09-30"
+    assert q3res["matched"] == 2
+    assert q3res["skipped"] == ["Ghost Capital"]  # unknown member reported, not created
+
+    # No account was created for the unknown roster name.
+    assert session.exec(select(User).where(User.name == "Ghost Capital")).first() is None
+
+    # Alice now has two statements — a real trend line — and the latest (Q4) is intact.
+    stmts = session.exec(
+        select(CapitalAccountStatement)
+        .where(CapitalAccountStatement.investor_user_id == alice.id)
+        .order_by(CapitalAccountStatement.as_of_date)  # type: ignore[arg-type]
+    ).all()
+    assert [s.as_of_date for s in stmts] == [date(2025, 9, 30), date(2025, 12, 31)]
+    assert [s.ending_balance_cents for s in stmts] == [42_000_000, 45_500_000]
+
+
+def test_batch_reimport_updates_in_place(auth_client, session):
+    fund = Entity(name="LTPF IV", type=EntityType.fund)
+    session.add(fund)
+    session.commit()
+    session.refresh(fund)
+    carol = make_user(session, username="carol", name="Carol Ira", role=UserRole.investor)
+
+    def one_file(ending: int) -> bytes:
+        return _alloc_si_file(datetime(2025, 12, 31),
+                              [{"id": "INV-1", "name": "Carol Ira", "ending": ending}])
+
+    for ending in (300_000, 315_000):  # corrected figure re-imported at the same quarter
+        resp = auth_client.post(
+            "/api/import/capital-accounts/batch",
+            data={"entity_id": fund.id},
+            files=[("files", ("f.xlsx", one_file(ending), "application/octet-stream"))],
+        )
+        assert resp.status_code == 200, resp.text
+
+    stmts = session.exec(
+        select(CapitalAccountStatement).where(CapitalAccountStatement.investor_user_id == carol.id)
+    ).all()
+    assert len(stmts) == 1                         # upsert, not a duplicate
+    assert stmts[0].ending_balance_cents == 31_500_000