refactor: restructure project configuration and utility modules

- Move configuration and utility files to more organized locations
- Update import paths across the project to reflect new file structure
- Simplify content and internationalization utilities
- Remove redundant configuration files and consolidate logic
- Add prefetch configuration to Astro config for improved performance

src/utils/content.config.ts

@@ -1,136 +0,0 @@
-import type { CollectionEntry } from 'astro:content'
-import themeConfig from '@/config'
-import { langPath } from '@/utils/ui'
-import { getCollection } from 'astro:content'
-
-export type Post = CollectionEntry<'posts'>
-export type PostData = Post['data']
-export type PostsGroupByYear = Map<number, Post[]>
-
-// Check if the slug is duplicated under the same language.
-export async function checkSlugDuplication(posts: Post[]): Promise<string[]> {
-  const slugMap = new Map<string, Set<string>>() // Map<lang, Set<slug>>
-  const duplicates: string[] = []
-
-  posts.forEach((post) => {
-    const lang = post.data.lang || ''
-    const slug = post.data.slug || post.slug
-
-    if (!slugMap.has(lang)) {
-      slugMap.set(lang, new Set())
-    }
-
-    const slugSet = slugMap.get(lang)!
-    if (slugSet.has(slug)) {
-      duplicates.push(`Duplicate slug "${slug}" found in language "${lang || 'default'}"`)
-    }
-    else {
-      slugSet.add(slug)
-    }
-  })
-
-  return duplicates
-}
-
-// Get all posts except drafts (include pinned)
-export async function getPosts(lang?: string) {
-  const defaultLocale = themeConfig.global.locale
-  const currentLang = lang || defaultLocale
-
-  const posts = await getCollection(
-    'posts',
-    ({ data }: Post) => {
-      const shouldInclude = import.meta.env.DEV || !data.draft
-      if (!langPath.includes(currentLang)) {
-        return shouldInclude && data.lang === ''
-      }
-      return shouldInclude && (data.lang === currentLang || data.lang === '')
-    },
-  )
-
-  return posts.sort((a: Post, b: Post) =>
-    b.data.published.valueOf() - a.data.published.valueOf(),
-  )
-}
-
-// Get all posts except drafts (not pinned)
-export async function getRegularPosts(lang?: string) {
-  const posts = await getPosts(lang)
-  return posts.filter(post => !post.data.pin)
-}
-
-// Get pinned posts
-export async function getPinnedPosts(lang?: string) {
-  const posts = await getPosts(lang)
-  return posts.filter(post => post.data.pin)
-}
-
-// Get posts group by year (not pinned)
-export async function getPostsByYear(lang?: string): Promise<PostsGroupByYear> {
-  const posts = await getRegularPosts(lang)
-  const yearMap = new Map<number, Post[]>()
-
-  posts.forEach((post: Post) => {
-    const year = post.data.published.getFullYear()
-    if (!yearMap.has(year)) {
-      yearMap.set(year, [])
-    }
-    yearMap.get(year)?.push(post)
-  })
-
-  yearMap.forEach((yearPosts) => {
-    yearPosts.sort((a: Post, b: Post) => {
-      const aDate = a.data.published
-      const bDate = b.data.published
-      const monthDiff = bDate.getMonth() - aDate.getMonth()
-
-      if (monthDiff !== 0) {
-        return monthDiff
-      }
-      return bDate.getDate() - aDate.getDate()
-    })
-  })
-
-  return new Map([...yearMap.entries()].sort((a, b) => b[0] - a[0]))
-}
-
-// Get all tags
-export async function getAllTags(lang?: string) {
-  const posts = await getPosts(lang)
-  const tags = new Set<string>()
-
-  posts.forEach((post: Post) => {
-    post.data.tags?.forEach((tag: string) =>
-      tags.add(tag),
-    )
-  })
-
-  return Array.from(tags)
-}
-
-// Get posts group by each tag
-export async function getPostsGroupByTags(lang?: string) {
-  const posts = await getRegularPosts(lang)
-  const tagMap = new Map<string, Post[]>()
-
-  posts.forEach((post: Post) => {
-    if (post.data.tags && post.data.tags.length > 0) {
-      post.data.tags.forEach((tag: string) => {
-        if (!tagMap.has(tag)) {
-          tagMap.set(tag, [])
-        }
-        tagMap.get(tag)?.push(post)
-      })
-    }
-  })
-
-  return tagMap
-}
-
-// Get all posts by one tag
-export async function getPostsByTag(tag: string, lang?: string) {
-  const posts = await getRegularPosts(lang)
-  return posts.filter((post: Post) =>
-    post.data.tags?.includes(tag),
-  )
-}