release: v1.2.8 — 双域名保存确认与 clear-domains 恢复

启用双域名时以确认框提示锁死风险与恢复方式，不再强制校验 Host。
新增 clear-domains 运维 CLI 与相关文档。

server/cli/clear-domains.mjs

@@ -0,0 +1,60 @@
+import { mkdirSync } from 'node:fs'
+import { join } from 'node:path'
+import { DatabaseSync } from 'node:sqlite'
+
+const SITE_KEY = 'site_base_url'
+const IMAGE_KEY = 'image_base_url'
+
+const args = process.argv.slice(2)
+const siteOnly = args.includes('--site')
+const imageOnly = args.includes('--image')
+
+if (args.some(arg => arg.startsWith('--') && arg !== '--site' && arg !== '--image')) {
+  console.error('Usage: clear-domains [--site] [--image]')
+  console.error('  (no flags)  Clear both site and image URLs from settings')
+  console.error('  --site      Clear site URL only')
+  console.error('  --image     Clear image URL only')
+  process.exit(1)
+}
+
+if (siteOnly && imageOnly) {
+  console.error('Usage: specify at most one of --site or --image')
+  process.exit(1)
+}
+
+const dataDir = process.env.DATA_DIR || join(process.cwd(), 'data')
+mkdirSync(dataDir, { recursive: true })
+const db = new DatabaseSync(join(dataDir, 'pichost.db'))
+
+function readSetting(key) {
+  const row = db.prepare(`
+    SELECT value
+    FROM settings
+    WHERE key = ?
+  `).get(key)
+  return row?.value ?? null
+}
+
+const beforeSite = readSetting(SITE_KEY)
+const beforeImage = readSetting(IMAGE_KEY)
+
+const keysToClear = siteOnly
+  ? [SITE_KEY]
+  : imageOnly
+    ? [IMAGE_KEY]
+    : [SITE_KEY, IMAGE_KEY]
+
+for (const key of keysToClear) {
+  db.prepare('DELETE FROM settings WHERE key = ?').run(key)
+}
+
+db.close()
+
+console.log('[PicHost] Domain settings cleared from database.')
+if (keysToClear.includes(SITE_KEY)) {
+  console.log(`  site_base_url: ${beforeSite ?? '(unset)'} → (removed)`)
+}
+if (keysToClear.includes(IMAGE_KEY)) {
+  console.log(`  image_base_url: ${beforeImage ?? '(unset)'} → (removed)`)
+}
+console.log('[PicHost] Restart is not required. Refresh the admin page or use your previous access URL.')