fix add errors

src/fastapi_app/lib/api/v1/handlers/health/__init__.py

@@ -0,0 +1,5 @@
+from .liveness_probe import router as health_router
+
+__all__ = [
+    "health_router",
+]

src/fastapi_app/lib/app/errors.py

@@ -0,0 +1,22 @@
+import typing
+
+
+class ApplicationError(Exception):
+    def __init__(self, message: str, *args: typing.Any) -> None:
+        super().__init__(*args)
+        self.message = message
+
+
+class DisposeError(ApplicationError):
+    pass
+
+
+class StartServerError(ApplicationError):
+    pass
+
+
+__all__ = [
+    "ApplicationError",
+    "DisposeError",
+    "StartServerError",
+]