Refactor code for improved readability and consistency

- Reformatted function signatures in `organization_service.py` and `task_service.py` for better alignment.
- Updated import statements across multiple files for consistency and organization.
- Enhanced test files by improving formatting and ensuring consistent use of async session factories.
- Added type hints and improved type safety in various service and test files.
- Adjusted `pyproject.toml` to include configuration for isort, mypy, and ruff for better code quality checks.
- Cleaned up unused imports and organized existing ones in several test files.

tests/services/test_activity_service.py

@@ -1,14 +1,12 @@
 """Unit tests for ActivityService."""
+
 from __future__ import annotations
 
-from collections.abc import AsyncGenerator
 import uuid
+from collections.abc import AsyncGenerator
 
 import pytest
 import pytest_asyncio
-from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
-from sqlalchemy.pool import StaticPool
-
 from app.models.activity import Activity, ActivityType
 from app.models.base import Base
 from app.models.contact import Contact
@@ -24,6 +22,8 @@ from app.services.activity_service import (
     ActivityValidationError,
 )
 from app.services.organization_service import OrganizationContext
+from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
+from sqlalchemy.pool import StaticPool
 
 
 @pytest_asyncio.fixture()
@@ -91,9 +91,16 @@ async def test_list_activities_returns_only_current_deal(session: AsyncSession)
 
     session.add_all(
         [
-            Activity(deal_id=deal_id, author_id=context.user_id, type=ActivityType.COMMENT, payload={"text": "hi"}),
-            Activity(deal_id=deal_id + 1, author_id=context.user_id, type=ActivityType.SYSTEM, payload={}),
-        ]
+            Activity(
+                deal_id=deal_id,
+                author_id=context.user_id,
+                type=ActivityType.COMMENT,
+                payload={"text": "hi"},
+            ),
+            Activity(
+                deal_id=deal_id + 1, author_id=context.user_id, type=ActivityType.SYSTEM, payload={}
+            ),
+        ],
     )
     await session.flush()
 
@@ -112,7 +119,9 @@ async def test_add_comment_rejects_empty_text(session: AsyncSession) -> None:
     service = ActivityService(repository=repo)
 
     with pytest.raises(ActivityValidationError):
-        await service.add_comment(deal_id=deal_id, author_id=context.user_id, text="   ", context=context)
+        await service.add_comment(
+            deal_id=deal_id, author_id=context.user_id, text="   ", context=context
+        )
 
 
 @pytest.mark.asyncio