chore: 删除冗余的 Modal.vue

项目已有 BaseDialog.vue 组件提供相同功能，此组件属于误提交。

frontend/src/components/common/Modal.vue

-<template>
-  <Teleport to="body">
-    <div
-      v-if="show"
-      class="modal-overlay"
-      aria-labelledby="modal-title"
-      role="dialog"
-      aria-modal="true"
-      @click.self="handleClose"
-    >
-      <!-- Modal panel -->
-      <div :class="['modal-content', sizeClasses]" @click.stop>
-        <!-- Header -->
-        <div class="modal-header">
-          <h3 id="modal-title" class="modal-title">
-            {{ title }}
-          </h3>
-          <button
-            @click="emit('close')"
-            class="-mr-2 rounded-xl p-2 text-gray-400 transition-colors hover:bg-gray-100 hover:text-gray-600 dark:text-dark-500 dark:hover:bg-dark-700 dark:hover:text-dark-300"
-            aria-label="Close modal"
-          >
-            <svg
-              class="h-5 w-5"
-              fill="none"
-              stroke="currentColor"
-              viewBox="0 0 24 24"
-              stroke-width="1.5"
-            >
-              <path stroke-linecap="round" stroke-linejoin="round" d="M6 18L18 6M6 6l12 12" />
-            </svg>
-          </button>
-        </div>
-
-        <!-- Body -->
-        <div class="modal-body">
-          <slot></slot>
-        </div>
-
-        <!-- Footer -->
-        <div v-if="$slots.footer" class="modal-footer">
-          <slot name="footer"></slot>
-        </div>
-      </div>
-    </div>
-  </Teleport>
-</template>
-
-<script setup lang="ts">
-import { computed, watch, onMounted, onUnmounted } from 'vue'
-
-type ModalSize = 'sm' | 'md' | 'lg' | 'xl' | '2xl' | 'full'
-
-interface Props {
-  show: boolean
-  title: string
-  size?: ModalSize
-  closeOnEscape?: boolean
-  closeOnClickOutside?: boolean
-}
-
-interface Emits {
-  (e: 'close'): void
-}
-
-const props = withDefaults(defineProps<Props>(), {
-  size: 'md',
-  closeOnEscape: true,
-  closeOnClickOutside: false
-})
-
-const emit = defineEmits<Emits>()
-
-const sizeClasses = computed(() => {
-  const sizes: Record<ModalSize, string> = {
-    sm: 'max-w-sm',
-    md: 'max-w-md',
-    lg: 'max-w-lg',
-    xl: 'max-w-xl',
-    '2xl': 'max-w-5xl',
-    full: 'max-w-4xl'
-  }
-  return sizes[props.size]
-})
-
-const handleClose = () => {
-  if (props.closeOnClickOutside) {
-    emit('close')
-  }
-}
-
-const handleEscape = (event: KeyboardEvent) => {
-  if (props.show && props.closeOnEscape && event.key === 'Escape') {
-    emit('close')
-  }
-}
-
-// Prevent body scroll when modal is open
-watch(
-  () => props.show,
-  (isOpen) => {
-    console.log('[Modal] show changed to:', isOpen)
-    if (isOpen) {
-      document.body.style.overflow = 'hidden'
-    } else {
-      document.body.style.overflow = ''
-    }
-  },
-  { immediate: true }
-)
-
-onMounted(() => {
-  document.addEventListener('keydown', handleEscape)
-})
-
-onUnmounted(() => {
-  document.removeEventListener('keydown', handleEscape)
-  document.body.style.overflow = ''
-})
-</script>