fix(send-routing): address final code review findings

- WeComBotSender.resolveWebhookUrl: use custom URL as-is when no %s placeholder
- WeComBotSender: treat unparseable/blank response body as failure
- ConversationService.isAccountCompatibleWithConversation: ignore scene for single chats
- SendService.selectSendAccountCandidates: apply accountTypes filter for non-conversation records
- SendService: replace account type magic numbers with AccountType constants
- WeComChannelAdapter: use AccountType.WECOM_BOT.getCode() instead of literal 6
- admin-web Conversation.vue: fallback to channelType filter when scene is unset
- add tests for single-chat null scene, webhook_url propagation, and custom URL without %s

backend/mci-channel-wecom/src/main/java/com/sino/mci/channel/wecom/WeComBotSender.java

@@ -62,6 +62,11 @@ public class WeComBotSender {
             String url = resolveWebhookUrl(request.getExtra(), key);
             ResponseEntity<String> response = restTemplate.postForEntity(url, entity, String.class);
             Map<String, Object> responseBody = parseResponseBody(response.getBody());
+            if (responseBody == null) {
+                result.setSuccess(false);
+                result.setMessage("企微群机器人返回无法解析的响应");
+                return result;
+            }
             int errcode = parseInt(responseBody.get("errcode"));
             if (errcode != 0) {
                 result.setSuccess(false);
@@ -88,21 +93,20 @@ public class WeComBotSender {
             if (customUrl.contains("%s")) {
                 return customUrl.replace("%s", key);
             }
-            log.warn("[WeComBot] custom webhook_url missing %s placeholder; appending key param");
-            return customUrl.contains("?") ? customUrl + "&key=" + key : customUrl + "?key=" + key;
+            return customUrl;
         }
         return String.format(DEFAULT_WEBHOOK_URL, key);
     }
 
     private Map<String, Object> parseResponseBody(String body) {
         if (body == null || body.isBlank()) {
-            return new HashMap<>();
+            return null;
         }
         try {
             return objectMapper.readValue(body, Map.class);
         } catch (Exception e) {
             log.warn("[WeComBot] 解析响应失败: {}", body, e);
-            return new HashMap<>();
+            return null;
         }
     }
 

backend/mci-channel-wecom/src/main/java/com/sino/mci/channel/wecom/WeComChannelAdapter.java

@@ -5,6 +5,7 @@ import com.sino.mci.channel.common.dto.ChannelInitRequest;
 import com.sino.mci.channel.common.dto.ChannelInitResult;
 import com.sino.mci.channel.common.dto.SendMessageRequest;
 import com.sino.mci.channel.common.dto.SendMessageResult;
+import com.sino.mci.channel.common.model.AccountType;
 import com.sino.mci.channel.common.model.ChannelType;
 import com.sino.mci.channel.common.spi.ChannelAdapter;
 import com.sino.mci.channel.wecom.support.WeComServiceFactory;
@@ -86,7 +87,7 @@ public class WeComChannelAdapter implements ChannelAdapter {
         }
 
         Integer accountType = getAccountType(request);
-        if (accountType != null && accountType == 6) {
+        if (accountType != null && accountType == AccountType.WECOM_BOT.getCode()) {
             return weComBotSender.send(request);
         }
 

backend/mci-channel-wecom/src/test/java/com/sino/mci/channel/wecom/WeComBotSenderTest.java

@@ -109,4 +109,33 @@ class WeComBotSenderTest {
         assertTrue(result.isSuccess(), result.getMessage());
         server.verify();
     }
+
+    @Test
+    void sendUsesCustomWebhookUrlWithoutPlaceholder() throws Exception {
+        server.expect(requestTo("https://qyapi.weixin.qq.com/cgi-bin/webhook/send?key=REALKEY"))
+                .andExpect(content().json("{\"msgtype\":\"text\",\"text\":{\"content\":\"hello\"}}"))
+                .andRespond(withSuccess("{\"errcode\":0,\"errmsg\":\"ok\"}", MediaType.APPLICATION_JSON));
+
+        SendMessageRequest request = new SendMessageRequest();
+        request.setExtra(Map.of("account_id", "dummy", "webhook_url", "https://qyapi.weixin.qq.com/cgi-bin/webhook/send?key=REALKEY"));
+        request.setContentType("text");
+        request.setContent(Map.of("text", "hello"));
+        SendMessageResult result = sender.send(request);
+        assertTrue(result.isSuccess(), result.getMessage());
+        server.verify();
+    }
+
+    @Test
+    void sendFailsOnUnparseableResponseBody() {
+        server.expect(requestTo("https://qyapi.weixin.qq.com/cgi-bin/webhook/send?key=dummy"))
+                .andRespond(withSuccess("not-json", MediaType.TEXT_PLAIN));
+
+        SendMessageRequest request = new SendMessageRequest();
+        request.setExtra(Map.of("account_id", "dummy"));
+        request.setContentType("text");
+        request.setContent(Map.of("text", "hello"));
+        SendMessageResult result = sender.send(request);
+        assertFalse(result.isSuccess());
+        assertTrue(result.getMessage().contains("无法解析"));
+    }
 }