fix(tests): isolate SQLite test databases

Co-authored-by: OpenAI/GPT-5.6-Terra <vibecoder@antoineve.me>

tests/conftest.py

@@ -2,6 +2,7 @@ import pytest
 
 from app import create_app
 from app import db as _db
+from tests.in_memory_db import IN_MEMORY_DATABASE_URI, in_memory_engine_options
 
 
 @pytest.fixture
@@ -72,9 +73,12 @@ forfait = 0
         encoding="utf-8",
     )
 
-    application = create_app(config_path=str(config_path))
+    application = create_app(
+        config_path=str(config_path),
+        database_uri=IN_MEMORY_DATABASE_URI,
+        engine_options=in_memory_engine_options(),
+    )
     application.config["TESTING"] = True
-    application.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///:memory:"
 
     with application.app_context():
         _db.create_all()