🎉 Initial commit: Document Server MVP

✨ Features implemented:
- FastAPI backend with JWT authentication
- PostgreSQL database with async SQLAlchemy
- HTML document viewer with smart highlighting
- Note system connected to highlights (1:1 relationship)
- Bookmark system for quick navigation
- Integrated search (documents + notes)
- Tag system for document organization
- Docker containerization with Nginx

🔧 Technical stack:
- Backend: FastAPI + PostgreSQL + Redis
- Frontend: Alpine.js + Tailwind CSS
- Authentication: JWT tokens
- File handling: HTML + PDF support
- Search: Full-text search with relevance scoring

📋 Core functionality:
- Text selection → Highlight creation
- Highlight → Note attachment
- Note management with search/filtering
- Bookmark creation at scroll positions
- Document upload with metadata
- User management (admin creates accounts)

backend/src/models/note.py

@@ -0,0 +1,47 @@
+"""
+메모 모델
+"""
+from sqlalchemy import Column, String, DateTime, Text, Boolean, ForeignKey
+from sqlalchemy.dialects.postgresql import UUID, ARRAY
+from sqlalchemy.orm import relationship
+from sqlalchemy.sql import func
+import uuid
+
+from src.core.database import Base
+
+
+class Note(Base):
+    """메모 테이블 (하이라이트와 1:1 관계)"""
+    __tablename__ = "notes"
+
+    id = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    
+    # 연결 정보
+    highlight_id = Column(UUID(as_uuid=True), ForeignKey("highlights.id"), nullable=False, unique=True)
+    
+    # 메모 내용
+    content = Column(Text, nullable=False)
+    is_private = Column(Boolean, default=True)  # 개인 메모 여부
+    
+    # 태그 (메모 분류용)
+    tags = Column(ARRAY(String), nullable=True)  # ["중요", "질문", "아이디어"]
+    
+    # 메타데이터
+    created_at = Column(DateTime(timezone=True), server_default=func.now())
+    updated_at = Column(DateTime(timezone=True), onupdate=func.now())
+    
+    # 관계
+    highlight = relationship("Highlight", back_populates="note")
+
+    @property
+    def user_id(self):
+        """하이라이트를 통해 사용자 ID 가져오기"""
+        return self.highlight.user_id if self.highlight else None
+
+    @property
+    def document_id(self):
+        """하이라이트를 통해 문서 ID 가져오기"""
+        return self.highlight.document_id if self.highlight else None
+
+    def __repr__(self):
+        return f"<Note(id='{self.id}', content='{self.content[:50]}...')>"