0.2.24: household-aware GP asset balances + show on Overview

Fixes a linked GP entity showing an empty Assets tab when its capital is
held under the linked account's other legal names (the eNAV often splits
one LLC across names).

- New GET /api/entities/{id}/asset-balances: household-aware, returns the
  linked account's (and its linked names') capital balances per fund, plus
  the linked account name for a clear empty state.
- Assets tab uses it; shows "linked to X but no balances on file" instead
  of a blank table when the wrong account is linked.
- GP/mgmt Overview now surfaces the total linked balance across funds with
  a "View by fund" link, so assets are visible without opening the tab.

Verified: 15/15 backend tests (incl. household case); frontend tsc + vite
build clean.

backend/ten31portal/routers/entity_router.py

@@ -7,7 +7,8 @@ from sqlmodel import Session, col, select
 
 from ten31portal.audit import record_audit
 from ten31portal.auth import (
-    accessible_entity_ids, get_current_user, require_internal, require_writer,
+    accessible_entity_ids, get_current_user, household_user_ids, require_internal,
+    require_writer,
 )
 from ten31portal.database import get_session
 from ten31portal.models import (
@@ -15,8 +16,8 @@ from ten31portal.models import (
     Position, UserRole, Valuation, ValuationRound, RoundStatus, User,
 )
 from ten31portal.schemas import (
-    EntityCreate, EntityResponse, EntityStakeCreate, EntityStakeResponse, EntityUpdate,
-    PartnerResponse,
+    AssetBalancesResponse, CapitalAccountResponse, EntityCreate, EntityResponse,
+    EntityStakeCreate, EntityStakeResponse, EntityUpdate, PartnerResponse,
 )
 
 router = APIRouter(prefix="/api/entities", tags=["entities"])
@@ -222,6 +223,45 @@ def update_entity(
     return EntityResponse.model_validate(entity, from_attributes=True)
 
 
+@router.get("/{entity_id}/asset-balances")
+def asset_balances(
+    entity_id: int,
+    user: User = Depends(require_internal),
+    session: Session = Depends(get_session),
+) -> AssetBalancesResponse:
+    """A GP/mgmt entity's assets = the linked account's capital balances across the funds.
+
+    Household-aware: if the linked account has other legal names linked to it (as the eNAV
+    often splits one LLC across names), their balances are included too.
+    """
+    entity = session.get(Entity, entity_id)
+    if entity is None:
+        raise HTTPException(status_code=404, detail="Entity not found")
+    if entity.linked_user_id is None:
+        return AssetBalancesResponse()
+    linked = session.get(User, entity.linked_user_id)
+    if linked is None:
+        return AssetBalancesResponse(linked_user_id=entity.linked_user_id)
+
+    household = household_user_ids(linked, session)
+    rows = session.exec(
+        select(CapitalAccountStatement)
+        .where(col(CapitalAccountStatement.investor_user_id).in_(household))
+        .order_by(col(CapitalAccountStatement.as_of_date).desc())
+    ).all()
+    names = dict(session.exec(
+        select(User.id, User.name).where(col(User.id).in_({r.investor_user_id for r in rows}))
+    ).all()) if rows else {}
+    balances: list[CapitalAccountResponse] = []
+    for r in rows:
+        d = CapitalAccountResponse.model_validate(r, from_attributes=True)
+        d.investor_name = names.get(r.investor_user_id)
+        balances.append(d)
+    return AssetBalancesResponse(
+        linked_user_id=linked.id, linked_name=linked.name, balances=balances,
+    )
+
+
 # --- Entity stakes: a GP/mgmt entity's interest in the funds it manages ---
 
 def _stake_response(stake: EntityStake, funds: dict[int, Entity]) -> EntityStakeResponse: