REFACTOR(repo): simplify project structure

- Move services/nextjs to nextjs/
- Move deploy/docker/Dockerfile.prod to Dockerfile
- Add GitHub Actions workflows (ci.yml, build.yml)
- Remove deploy/, services/, scripts/ folders

nextjs/src/entities/todo/ui/TodoItem.tsx

@@ -0,0 +1,132 @@
+'use client'
+
+import { Todo } from '../model/types'
+import { Checkbox } from '@/shared/ui/checkbox'
+import { Button } from '@/shared/ui/button'
+import { Trash2, Edit2 } from 'lucide-react'
+import { cn } from '@/shared/lib/utils'
+import { useState } from 'react'
+import { Input } from '@/shared/ui/input'
+
+interface TodoItemProps {
+  todo: Todo
+  onToggle: (id: string) => void
+  onDelete: (id: string) => void
+  onUpdate: (id: string, title: string, description?: string) => void
+}
+
+export function TodoItem({ todo, onToggle, onDelete, onUpdate }: TodoItemProps) {
+  const [isEditing, setIsEditing] = useState(false)
+  const [editTitle, setEditTitle] = useState(todo.title)
+  const [editDescription, setEditDescription] = useState(todo.description || '')
+
+  const handleSave = () => {
+    if (editTitle.trim()) {
+      onUpdate(todo.id, editTitle, editDescription)
+      setIsEditing(false)
+    }
+  }
+
+  const handleCancel = () => {
+    setEditTitle(todo.title)
+    setEditDescription(todo.description || '')
+    setIsEditing(false)
+  }
+
+  if (isEditing) {
+    return (
+      <div className="flex flex-col gap-2 p-3 border rounded-lg bg-background">
+        <Input
+          value={editTitle}
+          onChange={(e) => setEditTitle(e.target.value)}
+          placeholder="Todo 제목"
+          className="font-medium"
+          autoFocus
+          onKeyDown={(e) => {
+            if (e.key === 'Enter' && !e.shiftKey) {
+              e.preventDefault()
+              handleSave()
+            } else if (e.key === 'Escape') {
+              handleCancel()
+            }
+          }}
+        />
+        <Input
+          value={editDescription}
+          onChange={(e) => setEditDescription(e.target.value)}
+          placeholder="설명 (선택사항)"
+          onKeyDown={(e) => {
+            if (e.key === 'Enter' && !e.shiftKey) {
+              e.preventDefault()
+              handleSave()
+            } else if (e.key === 'Escape') {
+              handleCancel()
+            }
+          }}
+        />
+        <div className="flex gap-2 justify-end">
+          <Button size="sm" variant="ghost" onClick={handleCancel}>
+            취소
+          </Button>
+          <Button size="sm" onClick={handleSave}>
+            저장
+          </Button>
+        </div>
+      </div>
+    )
+  }
+
+  return (
+    <div
+      className={cn(
+        "flex items-start gap-3 p-3 rounded-lg border bg-background",
+        "hover:bg-accent/50 transition-colors group"
+      )}
+    >
+      <Checkbox
+        checked={todo.completed}
+        onCheckedChange={() => onToggle(todo.id)}
+        className="mt-0.5"
+      />
+      
+      <div className="flex-1 min-w-0">
+        <div
+          className={cn(
+            "font-medium text-sm",
+            todo.completed && "line-through text-muted-foreground"
+          )}
+        >
+          {todo.title}
+        </div>
+        {todo.description && (
+          <div className="text-xs text-muted-foreground mt-1">
+            {todo.description}
+          </div>
+        )}
+        <div className="text-xs text-muted-foreground mt-1">
+          {new Date(todo.createdAt).toLocaleDateString('ko-KR')}
+        </div>
+      </div>
+
+      <div className="flex gap-1 opacity-0 group-hover:opacity-100 transition-opacity">
+        <Button
+          size="icon"
+          variant="ghost"
+          className="h-8 w-8"
+          onClick={() => setIsEditing(true)}
+        >
+          <Edit2 className="h-4 w-4" />
+        </Button>
+        <Button
+          size="icon"
+          variant="ghost"
+          className="h-8 w-8 text-destructive hover:text-destructive"
+          onClick={() => onDelete(todo.id)}
+        >
+          <Trash2 className="h-4 w-4" />
+        </Button>
+      </div>
+    </div>
+  )
+}
+