🐛 修复小程序重新授权因空账号判空失败报 500 且 openid 无法绑定

system 侧 R.data(null) 被空值序列化写成 {}，Feign 侧反序列化出 id 为空的
MpUser 而非 null，被当作「已查到」：换号撞键分支误置 openidOccupied，导致
openid 永不绑定并提示「该微信已绑定其他账号」；手机号查不到账号时还会以
空主键、空租户调用 bindOpenId，系统侧判缺参 400，再被 Feign 降级包成
AssertionError（Error 而非 Exception）逃出 catch (Exception)，登录返回 500。

- 新增 presentAccount()：以主键判定是否命中，findByOpenid/findByPhone 统一走它
- bindOpenid 入口加守卫：缺主键或租户只记 WARN 后跳过，不再发空参数请求
- 补 2 条单测：空对象 data 视为未命中；不落空主键账号、不发空主键绑定

blade-auth/src/main/java/org/springblade/auth/support/MpLoginSupport.java

@@ -144,7 +144,7 @@ public class MpLoginSupport {
 		}
 		try {
 			R<MpUser> result = mpUserClient.userByOpenid(tenantId, openid);
-			return isSuccess(result) ? result.getData() : null;
+			return presentAccount(isSuccess(result) ? result.getData() : null);
 		} catch (Exception exception) {
 			// 查询失败按未命中处理，随后由 ensureUser 触达系统服务并兜住建号失败
 			log.warn("按 openid 查询小程序账号失败：租户={} openid={}", tenantId, openid, exception);
@@ -155,13 +155,25 @@ public class MpLoginSupport {
 	private MpUser findByPhone(String tenantId, String phone) {
 		try {
 			R<MpUser> result = mpUserClient.userByPhone(tenantId, phone);
-			return isSuccess(result) ? result.getData() : null;
+			return presentAccount(isSuccess(result) ? result.getData() : null);
 		} catch (Exception exception) {
 			log.warn("按手机号查询小程序账号失败：租户={} 手机号={}", tenantId, phone, exception);
 			return null;
 		}
 	}
 
+	/**
+	 * 远端「查无此账号」不等于客户端拿到 null
+	 * <p>
+	 * 服务端 R.data(null) 落 HTTP 时被 null 空值序列化写成 {}（BladeBeanSerializerModifier 对
+	 * Object 属性 null 输出空对象），Feign 侧于是反序列化出一个 id 为空的 MpUser 实例而不是 null。
+	 * 调用方只判 null，会把「没查到」当成「查到了空账号」，越过 ensureUser 建号并带着空主键去改库。
+	 * 故一律以主键判定是否命中。
+	 */
+	private static MpUser presentAccount(MpUser account) {
+		return account == null || account.getId() == null ? null : account;
+	}
+
 	/**
 	 * ② 查找或创建账号：登录路径上唯一允许让登录失败的动作
 	 */
@@ -267,6 +279,12 @@ public class MpLoginSupport {
 		if (account == null || StringUtil.isBlank(openid)) {
 			return;
 		}
+		// 空主键/空租户来自「查无账号」被反序列化成空对象，绑定请求会被系统侧判为缺参 400
+		if (account.getId() == null || StringUtil.isBlank(account.getTenantId())) {
+			log.warn("小程序账号缺少主键或租户，跳过绑定 openid：租户={} 账号={} openid={}",
+				account.getTenantId(), account.getId(), openid);
+			return;
+		}
 		// 撞键场景 openid 已属于另一个账号，明确不迁移，也不再尝试绑定
 		if (openidOccupied) {
 			return;

blade-auth/src/test/java/org/springblade/auth/support/MpLoginSupportTest.java

@@ -229,6 +229,44 @@ class MpLoginSupportTest {
 		verify(mpUserClient, never()).bindOpenId(anyString(), anyLong(), anyString());
 	}
 
+	@Test
+	@DisplayName("远端查无账号返回空对象（id 为空）：按未命中建号，并用真实主键补绑 openid")
+	void emptyAccountFromRemoteIsTreatedAsMiss() {
+		// 服务端 R.data(null) 落 HTTP 是 {}，Feign 反序列化成 id 为空的 MpUser 而非 null
+		MpUser created = mpUser(61L, PHONE, null, "driver");
+		when(mpUserClient.userByOpenid(TENANT_ID, OPENID)).thenReturn(R.data(new MpUser()));
+		when(mpUserClient.userByPhone(TENANT_ID, PHONE)).thenReturn(R.data(new MpUser()));
+		when(mpUserClient.ensureUser(any(MpUserEnsureDTO.class))).thenReturn(R.data(created));
+		when(mpUserClient.bindOpenId(TENANT_ID, 61L, OPENID)).thenReturn(R.data(Boolean.TRUE));
+		when(mpUserClient.userInfoById(61L)).thenReturn(R.data(userInfo(created, "driver")));
+		when(driverClient.ensureProfile(any(DriverEnsureProfileDTO.class))).thenReturn(R.data(profileResult()));
+
+		OAuth2User user = mpLoginSupport.ensureLoginAccount(TENANT_ID, PHONE, OPENID);
+
+		assertNotNull(user);
+		assertEquals("61", user.getUserId());
+		assertNull(user.getDetail().get(MpLoginSupport.DETAIL_LOGIN_NOTICE), "不该出现换号撞键提示");
+		verify(mpUserClient).ensureUser(any(MpUserEnsureDTO.class));
+		verify(mpUserClient, never()).updateUser(any(MpUser.class));
+		verify(mpUserClient).bindOpenId(TENANT_ID, 61L, OPENID);
+	}
+
+	@Test
+	@DisplayName("两个查询都返回空对象时：不落空账号、不发起带空主键的绑定")
+	void emptyAccountDoesNotLeakNullIdentityIntoBind() {
+		MpUser created = mpUser(62L, PHONE, OPENID, "driver");
+		when(mpUserClient.userByOpenid(TENANT_ID, OPENID)).thenReturn(R.data(new MpUser()));
+		when(mpUserClient.userByPhone(TENANT_ID, PHONE)).thenReturn(R.data(new MpUser()));
+		when(mpUserClient.ensureUser(any(MpUserEnsureDTO.class))).thenReturn(R.data(created));
+		when(mpUserClient.userInfoById(62L)).thenReturn(R.data(userInfo(created, "driver")));
+		when(driverClient.ensureProfile(any(DriverEnsureProfileDTO.class))).thenReturn(R.data(profileResult()));
+
+		OAuth2User user = mpLoginSupport.ensureLoginAccount(TENANT_ID, PHONE, OPENID);
+
+		assertEquals("62", user.getUserId());
+		verify(mpUserClient, never()).bindOpenId(anyString(), anyLong(), anyString());
+	}
+
 	private MpUser mpUser(Long id, String phone, String openid, String identities) {
 		MpUser user = new MpUser();
 		user.setId(id);