test: add rule-case validator for no-reply and 🔚 injection paths

docs/rule-cases.json

@@ -0,0 +1,54 @@
+{
+  "config": {
+    "enabled": true,
+    "discordOnly": true,
+    "bypassUserIds": ["561921120408698910"],
+    "endSymbols": ["。", "！", "？", ".", "!", "?"]
+  },
+  "cases": [
+    {
+      "name": "non-discord skips gate",
+      "channel": "telegram",
+      "senderId": "u1",
+      "content": "hello",
+      "expect": {
+        "shouldUseNoReply": false,
+        "reason": "non_discord",
+        "injectEndMarker": false
+      }
+    },
+    {
+      "name": "bypass sender injects end marker",
+      "channel": "discord",
+      "senderId": "561921120408698910",
+      "content": "hello",
+      "expect": {
+        "shouldUseNoReply": false,
+        "reason": "bypass_sender",
+        "injectEndMarker": true
+      }
+    },
+    {
+      "name": "ending punctuation injects end marker",
+      "channel": "discord",
+      "senderId": "u2",
+      "content": "你好！",
+      "expect": {
+        "shouldUseNoReply": false,
+        "reason": "end_symbol:！",
+        "injectEndMarker": true
+      }
+    },
+    {
+      "name": "no ending punctuation triggers no-reply override",
+      "channel": "discord",
+      "senderId": "u2",
+      "content": "继续",
+      "expect": {
+        "shouldUseNoReply": true,
+        "reason": "rule_match_no_end_symbol",
+        "injectEndMarker": false
+      }
+    }
+  ]
+}