tests: deepen all suites (37→87 checks, 0 failures, 100% pass)

lisp/system-model-provider.lisp

@@ -133,3 +133,9 @@ If API-KEY is nil, reads from environment."
   "Verify that provider-openai-request returns :error for an unregistered provider."
   (let ((result (provider-openai-request "hello" "test" :provider :not-a-real-provider)))
     (fiveam:is (eq (getf result :status) :error))))
+
+(fiveam:test test-provider-config-registered
+  "A registered provider should return its configuration plist."
+  (let ((config (provider-config :openrouter)))
+    (fiveam:is (listp config))
+    (fiveam:is (getf config :base-url))))