Implement LLM-WP-0007: Kimi K3 default and EUR spend reporting

Add moonshotai/kimi-k3 as OpenRouter basemodel default after live smoke,
USD→EUR cost conversion, append-only usage ledger, and CLI run/cost/spend
week commands with token and euro reporting.

tests/test_package_exports.py

@@ -61,3 +61,21 @@ def test_wp_0006_profile_primitives_are_exported_from_package_root():
     for name in expected_names:
         assert hasattr(llm_connect, name)
         assert name in llm_connect.__all__
+
+
+def test_wp_0007_spend_primitives_are_exported_from_package_root():
+    expected_names = [
+        "FxRate",
+        "resolve_fx_rate",
+        "UsageEvent",
+        "UsageLedger",
+        "UsageSummary",
+        "default_usage_ledger_path",
+        "event_from_response",
+        "maybe_record_usage",
+        "week_window",
+    ]
+
+    for name in expected_names:
+        assert hasattr(llm_connect, name)
+        assert name in llm_connect.__all__