feat: implement task management module

Backend (FastAPI):
- Database migration for spaces, projects, task_statuses, tasks tables
- SQLAlchemy models with relationships
- Pydantic schemas for CRUD operations
- Spaces API: CRUD with soft delete
- Projects API: CRUD with auto-created default statuses
- Tasks API: CRUD, status change, assign, subtask support
- Permission middleware with Security Level filtering
- Subtask depth limit (max 2 levels)

Frontend (React + Vite):
- Layout component with navigation
- Spaces list page
- Projects list page
- Tasks list page with status management

Fixes:
- auth_client.py: use 'username' field for external API
- config.py: extend JWT expiry to 7 days
- auth/router.py: sync Redis session with JWT expiry

Tests: 36 passed (unit + integration)
E2E: All APIs verified with real authentication

OpenSpec: add-task-management archived

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/schemas/__init__.py

@@ -2,6 +2,15 @@ from app.schemas.auth import LoginRequest, LoginResponse, TokenPayload
 from app.schemas.user import UserCreate, UserUpdate, UserResponse, UserInDB
 from app.schemas.department import DepartmentCreate, DepartmentUpdate, DepartmentResponse
 from app.schemas.role import RoleResponse
+from app.schemas.space import SpaceCreate, SpaceUpdate, SpaceResponse, SpaceWithOwner
+from app.schemas.project import (
+    ProjectCreate, ProjectUpdate, ProjectResponse, ProjectWithDetails, SecurityLevel
+)
+from app.schemas.task_status import TaskStatusCreate, TaskStatusUpdate, TaskStatusResponse
+from app.schemas.task import (
+    TaskCreate, TaskUpdate, TaskResponse, TaskWithDetails, TaskListResponse,
+    TaskStatusUpdate as TaskStatusChangeUpdate, TaskAssignUpdate, Priority
+)
 
 __all__ = [
     "LoginRequest",
@@ -15,4 +24,24 @@ __all__ = [
     "DepartmentUpdate",
     "DepartmentResponse",
     "RoleResponse",
+    "SpaceCreate",
+    "SpaceUpdate",
+    "SpaceResponse",
+    "SpaceWithOwner",
+    "ProjectCreate",
+    "ProjectUpdate",
+    "ProjectResponse",
+    "ProjectWithDetails",
+    "SecurityLevel",
+    "TaskStatusCreate",
+    "TaskStatusUpdate",
+    "TaskStatusResponse",
+    "TaskCreate",
+    "TaskUpdate",
+    "TaskResponse",
+    "TaskWithDetails",
+    "TaskListResponse",
+    "TaskStatusChangeUpdate",
+    "TaskAssignUpdate",
+    "Priority",
 ]

backend/app/schemas/project.py

@@ -0,0 +1,55 @@
+from pydantic import BaseModel
+from typing import Optional
+from datetime import datetime, date
+from decimal import Decimal
+from enum import Enum
+
+
+class SecurityLevel(str, Enum):
+    PUBLIC = "public"
+    DEPARTMENT = "department"
+    CONFIDENTIAL = "confidential"
+
+
+class ProjectBase(BaseModel):
+    title: str
+    description: Optional[str] = None
+    budget: Optional[Decimal] = None
+    start_date: Optional[date] = None
+    end_date: Optional[date] = None
+    security_level: SecurityLevel = SecurityLevel.DEPARTMENT
+
+
+class ProjectCreate(ProjectBase):
+    department_id: Optional[str] = None
+
+
+class ProjectUpdate(BaseModel):
+    title: Optional[str] = None
+    description: Optional[str] = None
+    budget: Optional[Decimal] = None
+    start_date: Optional[date] = None
+    end_date: Optional[date] = None
+    security_level: Optional[SecurityLevel] = None
+    status: Optional[str] = None
+    department_id: Optional[str] = None
+
+
+class ProjectResponse(ProjectBase):
+    id: str
+    space_id: str
+    owner_id: str
+    status: str
+    department_id: Optional[str] = None
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class ProjectWithDetails(ProjectResponse):
+    owner_name: Optional[str] = None
+    space_name: Optional[str] = None
+    department_name: Optional[str] = None
+    task_count: int = 0

backend/app/schemas/space.py

@@ -0,0 +1,32 @@
+from pydantic import BaseModel
+from typing import Optional
+from datetime import datetime
+
+
+class SpaceBase(BaseModel):
+    name: str
+    description: Optional[str] = None
+
+
+class SpaceCreate(SpaceBase):
+    pass
+
+
+class SpaceUpdate(BaseModel):
+    name: Optional[str] = None
+    description: Optional[str] = None
+
+
+class SpaceResponse(SpaceBase):
+    id: str
+    owner_id: str
+    is_active: bool
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class SpaceWithOwner(SpaceResponse):
+    owner_name: Optional[str] = None

backend/app/schemas/task.py

@@ -0,0 +1,74 @@
+from pydantic import BaseModel
+from typing import Optional, List
+from datetime import datetime
+from decimal import Decimal
+from enum import Enum
+
+
+class Priority(str, Enum):
+    LOW = "low"
+    MEDIUM = "medium"
+    HIGH = "high"
+    URGENT = "urgent"
+
+
+class TaskBase(BaseModel):
+    title: str
+    description: Optional[str] = None
+    priority: Priority = Priority.MEDIUM
+    original_estimate: Optional[Decimal] = None
+    due_date: Optional[datetime] = None
+
+
+class TaskCreate(TaskBase):
+    parent_task_id: Optional[str] = None
+    assignee_id: Optional[str] = None
+    status_id: Optional[str] = None
+
+
+class TaskUpdate(BaseModel):
+    title: Optional[str] = None
+    description: Optional[str] = None
+    priority: Optional[Priority] = None
+    original_estimate: Optional[Decimal] = None
+    time_spent: Optional[Decimal] = None
+    due_date: Optional[datetime] = None
+    position: Optional[int] = None
+
+
+class TaskStatusUpdate(BaseModel):
+    status_id: str
+
+
+class TaskAssignUpdate(BaseModel):
+    assignee_id: Optional[str] = None
+
+
+class TaskResponse(TaskBase):
+    id: str
+    project_id: str
+    parent_task_id: Optional[str] = None
+    assignee_id: Optional[str] = None
+    status_id: Optional[str] = None
+    time_spent: Decimal
+    blocker_flag: bool
+    position: int
+    created_by: str
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        from_attributes = True
+
+
+class TaskWithDetails(TaskResponse):
+    assignee_name: Optional[str] = None
+    status_name: Optional[str] = None
+    status_color: Optional[str] = None
+    creator_name: Optional[str] = None
+    subtask_count: int = 0
+
+
+class TaskListResponse(BaseModel):
+    tasks: List[TaskWithDetails]
+    total: int

backend/app/schemas/task_status.py

@@ -0,0 +1,30 @@
+from pydantic import BaseModel
+from typing import Optional
+from datetime import datetime
+
+
+class TaskStatusBase(BaseModel):
+    name: str
+    color: str = "#808080"
+    position: int = 0
+    is_done: bool = False
+
+
+class TaskStatusCreate(TaskStatusBase):
+    pass
+
+
+class TaskStatusUpdate(BaseModel):
+    name: Optional[str] = None
+    color: Optional[str] = None
+    position: Optional[int] = None
+    is_done: Optional[bool] = None
+
+
+class TaskStatusResponse(TaskStatusBase):
+    id: str
+    project_id: str
+    created_at: datetime
+
+    class Config:
+        from_attributes = True