接入 ESLint 并清理未使用代码

- 前后端接入 ESLint 10 扁平配置（typescript-eslint 类型感知检查 + react-hooks/react-refresh），新增 lint / lint:check / lint:fix 脚本并纳入 check 链路
- 清理全部 no-unused-vars 与 no-useless-assignment 警告，修复 floating promises、正则转义等问题
- 删除确认无引用的死代码（markKuaishouCloudBindUrlRefreshFailed、未使用 helper 等）

apps/backend/src/services/platforms/cloudtentacles/crypto-service.ts

@@ -48,7 +48,7 @@ export function encryptCloudtentaclesPayload(payload: JsonObject = {}, options:
       r: randomValue,
       plaintext,
     }
-  } catch (error) {
+  } catch {
     throw createHttpError('cloudtentacles 加密失败', {
       statusCode: 500,
       errorCode: 'cloudtentacles_encrypt_failed',

apps/backend/src/services/platforms/cloudtentacles/helpers.ts

@@ -220,11 +220,6 @@ function normalizePositiveInteger(value: unknown, fallback: number) {
   return Number.isInteger(parsed) && parsed > 0 ? parsed : fallback
 }
 
-function normalizeInteger(value: unknown, fallback: number) {
-  const parsed = Number(value)
-  return Number.isInteger(parsed) ? parsed : fallback
-}
-
 function normalizeHeaderMap(extra: unknown) {
   if (!extra || typeof extra !== 'object') {
     return {}

apps/backend/src/services/platforms/cloudtentacles/http-client.ts

@@ -339,7 +339,7 @@ async function waitForCloudtentaclesSlot(bucketKey: string, intervalMs: number)
 
   await previousQueue
 
-  let waitMs = 0
+  let waitMs
   try {
     const now = Date.now()
     const nextAvailableAt = bucketNextAvailableAt.get(bucketKey) || 0

apps/backend/src/services/platforms/kuaishou-industry/payload.ts

@@ -227,7 +227,7 @@ function assertCommonPayload(
     accessToken: string
     paramRaw: string
   },
-  config = assertKuaishouIndustryConfig(),
+  _config = assertKuaishouIndustryConfig(),
 ) {
   if (!payload.signMethod) {
     throw createHttpError('缺少 signMethod', {

apps/backend/src/services/platforms/kuaishou-industry/token-service.ts

@@ -377,7 +377,7 @@ async function saveTokenPayload(
   }
 }
 
-function normalizeTokenResponse(json: JsonObject, currentConfig: KuaishouIndustrySourceConfig) {
+function normalizeTokenResponse(json: JsonObject, _currentConfig: KuaishouIndustrySourceConfig) {
   const payload = isPlainObject(json.data) ? json.data : json
   const accessToken = pickFirstString(payload, ['access_token', 'accessToken', 'accessTokenValue'])
   const refreshToken = pickFirstString(payload, [