feat(logging): add pino dependency and LOG_LEVEL env var

src/env.mjs

@@ -19,6 +19,8 @@ export const env = createEnv({
     UPSTASH_REDIS_REST_TOKEN: z.string().min(1).optional(),
     // audit-P2-5: Cron job bearer token for /api/cron/* endpoints.
     CRON_SECRET: z.string().min(1).optional(),
+    // 日志级别控制（pino logger）
+    LOG_LEVEL: z.enum(["debug", "info", "warn", "error"]).default("info"),
   },
   client: {
     NEXT_PUBLIC_APP_URL: z.string().url().optional(),
@@ -37,6 +39,7 @@ export const env = createEnv({
     UPSTASH_REDIS_REST_URL: process.env.UPSTASH_REDIS_REST_URL,
     UPSTASH_REDIS_REST_TOKEN: process.env.UPSTASH_REDIS_REST_TOKEN,
     CRON_SECRET: process.env.CRON_SECRET,
+    LOG_LEVEL: process.env.LOG_LEVEL,
   },
   skipValidation: !!process.env.SKIP_ENV_VALIDATION,
   emptyStringAsUndefined: true,