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.

app/services/task_service.py

@@ -1,4 +1,5 @@
 """Business logic for tasks linked to deals."""
+
 from __future__ import annotations
 
 from collections.abc import Mapping, Sequence
@@ -9,10 +10,14 @@ from typing import Any
 from app.models.activity import ActivityCreate, ActivityType
 from app.models.organization_member import OrganizationRole
 from app.models.task import Task, TaskCreate
-from app.repositories.activity_repo import ActivityRepository, ActivityOrganizationMismatchError
+from app.repositories.activity_repo import ActivityOrganizationMismatchError, ActivityRepository
 from app.repositories.task_repo import (
     TaskAccessError as RepoTaskAccessError,
+)
+from app.repositories.task_repo import (
     TaskOrganizationMismatchError as RepoTaskOrganizationMismatchError,
+)
+from app.repositories.task_repo import (
     TaskQueryParams,
     TaskRepository,
 )