feat: CONAI Phase 1 MVP 초기 구현

소형 건설업체(100억 미만)를 위한 AI 기반 토목공사 통합관리 플랫폼

Backend (FastAPI):
- SQLAlchemy 모델 13개 (users, projects, wbs, tasks, daily_reports, reports, inspections, quality, weather, permits, rag, settings)
- API 라우터 11개 (auth, projects, tasks, daily_reports, reports, inspections, weather, rag, kakao, permits, settings)
- Services: Claude AI 래퍼, CPM Gantt 계산, 기상청 API, RAG(pgvector), 카카오 Skill API
- Alembic 마이그레이션 (pgvector 포함)
- pytest 테스트 (CPM, 날씨 경보)

Frontend (Next.js 15):
- 11개 페이지 (대시보드, 프로젝트, Gantt, 일보, 검측, 품질, 날씨, 인허가, RAG, 설정)
- TanStack Query + Zustand + Tailwind CSS

인프라:
- Docker Compose (PostgreSQL pgvector + backend + frontend)
- 한국어 README 및 설치 가이드

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/app/models/user.py

@@ -0,0 +1,31 @@
+import uuid
+from sqlalchemy import String, Boolean, Enum as SAEnum
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+from sqlalchemy.dialects.postgresql import UUID
+from app.core.database import Base
+from app.models.base import TimestampMixin, UUIDMixin
+import enum
+
+
+class UserRole(str, enum.Enum):
+    ADMIN = "admin"
+    SITE_MANAGER = "site_manager"
+    SUPERVISOR = "supervisor"
+    WORKER = "worker"
+
+
+class User(Base, UUIDMixin, TimestampMixin):
+    __tablename__ = "users"
+
+    email: Mapped[str] = mapped_column(String(255), unique=True, nullable=False, index=True)
+    hashed_password: Mapped[str] = mapped_column(String(255), nullable=False)
+    name: Mapped[str] = mapped_column(String(100), nullable=False)
+    role: Mapped[UserRole] = mapped_column(
+        SAEnum(UserRole, name="user_role"), default=UserRole.SITE_MANAGER, nullable=False
+    )
+    phone: Mapped[str | None] = mapped_column(String(20), nullable=True)
+    kakao_user_key: Mapped[str | None] = mapped_column(String(100), nullable=True, unique=True, index=True)
+    is_active: Mapped[bool] = mapped_column(Boolean, default=True, nullable=False)
+
+    # relationships
+    owned_projects: Mapped[list["Project"]] = relationship("Project", back_populates="owner", foreign_keys="Project.owner_id")