精简若干功能，优化slug生成规则

scripts/fetch_greetings.js

@@ -58,13 +58,13 @@ async function main() {
         }
     });
 
-    // Pick one random greeting per time slot, fall back to generic pool
+    // Keep all greetings per time slot (frontend picks randomly)
     var timeGreetings = {};
     timeKeys.forEach(function(key) {
         var list = byTime[key];
         if (list.length === 0) list = generic;
         if (list.length > 0) {
-            timeGreetings[key] = list[Math.floor(Math.random() * list.length)];
+            timeGreetings[key] = list;
         }
     });