fix: align portfolio-hub ledger write adapter to live API contract

REQ-017 CHG-20260606-01. Live portfolio-hub returned 404 for the
trex-orbit-assumed POST /v1/assets/{asset_id}/ledger/trades. Correct to
POST /v1/portfolios/{portfolio_id}/ledger/trades with body keys
quantity/fee_amount/tax_amount (was qty/fee/tax), success 201. Reverified
with live e2e (201 Created, outbox COMPLETED) + durability drain of the
prior 404'd item. Resolves the REL-001 ledger-write release blocker.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tests/adapters/ledger/test_portfolio_hub_ledger.py

@@ -1,6 +1,7 @@
 """portfolio-hub HTTP ledger adapter tests (REQ-017 AC-2/3)."""
 from __future__ import annotations
 
+import json
 from datetime import datetime, timezone
 
 import httpx
@@ -26,7 +27,7 @@ def _client(handler):
     return httpx.Client(transport=httpx.MockTransport(handler))
 
 
-def test_post_contract_includes_execution_id_and_path_uses_asset_id():
+def test_post_contract_includes_execution_id_and_path_uses_portfolio_id():
     captured = {}
 
     def handler(request: httpx.Request) -> httpx.Response:
@@ -38,9 +39,15 @@ def test_post_contract_includes_execution_id_and_path_uses_asset_id():
     adapter = PortfolioHubLedger("https://portfolio-hub.test", token="tok",
                                   client=_client(handler))
     adapter.record_trade(_trade(asset="PF-77"))
-    assert captured["url"] == "https://portfolio-hub.test/v1/assets/PF-77/ledger/trades"
-    assert "execution_id" in captured["body"]
-    assert "\"side\":\"buy\"" in captured["body"]
+    assert captured["url"] == "https://portfolio-hub.test/v1/portfolios/PF-77/ledger/trades"
+    body = json.loads(captured["body"])
+    # Live contract field names (REQ-017 CHG-04): quantity / fee_amount / tax_amount.
+    assert body["execution_id"] == "paper:PAPER-000001:10"
+    assert body["side"] == "buy"
+    assert body["quantity"] == 10
+    assert body["fee_amount"] == 1.5
+    assert body["tax_amount"] == 0.0
+    assert "qty" not in body and "fee" not in body and "tax" not in body
     assert captured["auth"] == "Bearer tok"