Implement rec - Phase 4 complete

tests/conftest.py

@@ -4,6 +4,7 @@ Every test gets a fresh in-memory SQLite database so tests are
 isolated, fast, and leave no artifacts on disk.
 """
 
+import os
 from pathlib import Path
 
 import pytest
@@ -28,9 +29,9 @@ from transcription.services.jobs import JobService
 def isolate_settings_from_local_env_files(tmp_path_factory):
     """Point `Settings` at a controlled stub env file instead of a developer one.
 
-    `Settings.model_config` declares `env_file=".env.production"`, resolved against the
-    current working directory, so a repository-root pytest run would otherwise read real
-    deployment values into tests that assert declared defaults.
+    `Settings()` resolves its env file through the shared config seam, so a repository-root
+    pytest run would otherwise read a developer's real `.env.production` into tests that
+    assert declared defaults.
 
     The stub mirrors what `.github/workflows/quality-gate.yml` writes in CI: only
     `OPENROUTER_API_KEY`, which is required and which many tests need `get_settings()` to
@@ -42,12 +43,15 @@ def isolate_settings_from_local_env_files(tmp_path_factory):
     stub = tmp_path_factory.mktemp("settings-env") / ".env.test"
     stub.write_text("OPENROUTER_API_KEY=test-placeholder-not-a-real-key\n", encoding="utf-8")
 
-    original = Settings.model_config.get("env_file")
-    Settings.model_config["env_file"] = str(stub)
+    original = os.environ.get("ENV_FILE")
+    os.environ["ENV_FILE"] = str(stub)
     try:
         yield
     finally:
-        Settings.model_config["env_file"] = original
+        if original is None:
+            os.environ.pop("ENV_FILE", None)
+        else:
+            os.environ["ENV_FILE"] = original
 
 
 @pytest.fixture