test(backend): add comprehensive tests for OAuth and agent endpoints

- Added tests for OAuth provider admin and consent endpoints covering edge cases.
- Extended agent-related tests to handle incorrect project associations and lifecycle state transitions.
- Introduced tests for sprint status transitions and validation checks.
- Improved multiline formatting consistency across all test functions.

backend/tests/api/dependencies/test_event_bus.py

@@ -0,0 +1,39 @@
+# tests/api/dependencies/test_event_bus.py
+"""Tests for the event_bus dependency."""
+
+from unittest.mock import AsyncMock, patch
+
+import pytest
+
+from app.api.dependencies.event_bus import get_event_bus
+from app.services.event_bus import EventBus
+
+
+@pytest.mark.asyncio
+class TestGetEventBusDependency:
+    """Tests for the get_event_bus FastAPI dependency."""
+
+    async def test_get_event_bus_returns_event_bus(self):
+        """Test that get_event_bus returns an EventBus instance."""
+        mock_event_bus = AsyncMock(spec=EventBus)
+
+        with patch(
+            "app.api.dependencies.event_bus._get_connected_event_bus",
+            return_value=mock_event_bus,
+        ):
+            result = await get_event_bus()
+
+            assert result is mock_event_bus
+
+    async def test_get_event_bus_calls_get_connected_event_bus(self):
+        """Test that get_event_bus calls the underlying function."""
+        mock_event_bus = AsyncMock(spec=EventBus)
+        mock_get_connected = AsyncMock(return_value=mock_event_bus)
+
+        with patch(
+            "app.api.dependencies.event_bus._get_connected_event_bus",
+            mock_get_connected,
+        ):
+            await get_event_bus()
+
+            mock_get_connected.assert_called_once()