release: v1.2.1 — login captcha, docs site, and bug fixes

Add slider captcha for web login, VitePress documentation on GitHub Pages,
and fixes for gallery delete refresh, pagination jump, and copy-format persistence.

server/utils/login-captcha.ts

@@ -0,0 +1,85 @@
+const TOLERANCE_PERCENT = 4
+const TTL_MS = 5 * 60 * 1000
+const TRACK_WIDTH = 320
+const TRACK_HEIGHT = 48
+const TRACK_INSET = 4
+const SLOT_SIZE = 40
+
+interface CaptchaChallenge {
+  targetPercent: number
+  expiresAt: number
+  confirmed: boolean
+}
+
+const challenges = new Map<string, CaptchaChallenge>()
+
+function purgeExpired() {
+  const now = Date.now()
+  for (const [id, challenge] of challenges) {
+    if (challenge.expiresAt <= now) {
+      challenges.delete(id)
+    }
+  }
+}
+
+function isPositionMatch(targetPercent: number, positionPercent: number): boolean {
+  return Math.abs(positionPercent - targetPercent) <= TOLERANCE_PERCENT
+}
+
+/** 缺口槽位 SVG（不返回 targetPercent 数字） */
+export function buildCaptchaTrackSvg(targetPercent: number): string {
+  const maxTravel = TRACK_WIDTH - SLOT_SIZE - TRACK_INSET * 2
+  const slotX = (TRACK_INSET + (targetPercent / 100) * maxTravel).toFixed(1)
+  const slotY = (TRACK_HEIGHT - SLOT_SIZE) / 2
+  return `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 ${TRACK_WIDTH} ${TRACK_HEIGHT}" width="100%" height="100%" preserveAspectRatio="none" aria-hidden="true">
+  <rect x="${slotX}" y="${slotY}" width="${SLOT_SIZE}" height="${SLOT_SIZE}" rx="6" fill="#64748b" opacity="0.14"/>
+</svg>`
+}
+
+export function createLoginCaptchaChallenge(): { id: string, svg: string } {
+  purgeExpired()
+  const id = crypto.randomUUID()
+  const targetPercent = Math.floor(20 + Math.random() * 61)
+  challenges.set(id, {
+    targetPercent,
+    expiresAt: Date.now() + TTL_MS,
+    confirmed: false
+  })
+  return { id, svg: buildCaptchaTrackSvg(targetPercent) }
+}
+
+export function confirmLoginCaptcha(id: string, positionPercent: number): boolean {
+  purgeExpired()
+  const challenge = challenges.get(id)
+  if (!challenge || challenge.expiresAt <= Date.now()) {
+    if (challenge) challenges.delete(id)
+    return false
+  }
+  if (!Number.isFinite(positionPercent)) return false
+  if (!isPositionMatch(challenge.targetPercent, positionPercent)) {
+    return false
+  }
+  challenge.confirmed = true
+  return true
+}
+
+export function verifyLoginCaptcha(id: string, positionPercent: number): boolean {
+  purgeExpired()
+  const challenge = challenges.get(id)
+  if (!challenge || challenge.expiresAt <= Date.now()) {
+    if (challenge) challenges.delete(id)
+    return false
+  }
+  if (!challenge.confirmed) return false
+  challenges.delete(id)
+  if (!Number.isFinite(positionPercent)) return false
+  return isPositionMatch(challenge.targetPercent, positionPercent)
+}
+
+export function __resetLoginCaptchaStoreForTests() {
+  challenges.clear()
+}
+
+export function __peekLoginCaptchaTargetForTests(id: string): number | undefined {
+  return challenges.get(id)?.targetPercent
+}