feat(hall): 站点主题中转 + 用户面站点信息端点（T2）——SiteOptionVo 扩 theme/themeParams（@JsonIgnoreProperties 兜未知键，兼容旧 CMS 三键形态，测试已证）；SiteDirectory 新增 findOption（resolveSite 的全量形态，resolveSite 委托之，SiteInfo 三字段不动）；HallController 新增 GET /api/hall/site（requireMember 同口径 + 防御性 SiteInfo 补壳）

src/test/java/com/yunhai/svchall/service/impl/CmsSiteDirectoryImplTest.java

@@ -128,6 +128,48 @@ class CmsSiteDirectoryImplTest {
         assertThrows(BizException.class, () -> directory.listSites(null));
     }
 
+    @Test
+    @DisplayName("T2 主题联动：theme/themeParams 随全量 VO 透传（findOption），resolveSite 三字段结构不变")
+    void findOption_mapsThemeFieldsThrough() {
+        SvcModels.SiteOptionVo row = vo("S1", "站点一", 1L);
+        row.setTheme("campus-glow");
+        row.getThemeParams().put("primary", "#0e8a5f");
+        when(openCall.getList(any(TargetSpec.class), eq(PATH), eq(Collections.emptyMap()), eq(VO_TYPE)))
+                .thenReturn(Collections.singletonList(row));
+
+        SvcModels.SiteOptionVo option = directory.findOption("S1");
+        assertEquals("S1", option.getSiteCode());
+        assertEquals("campus-glow", option.getTheme());
+        assertEquals("#0e8a5f", option.getThemeParams().get("primary"));
+        // resolveSite 委托 findOption：SiteInfo 三字段结构不动（避免 ripple）
+        SiteDirectory.SiteInfo site = directory.resolveSite("S1");
+        assertEquals("S1", site.getSiteCode());
+        assertEquals("站点一", site.getName());
+        assertEquals(1L, site.getSchId());
+        // 同一全量缓存：再取不重复出站
+        assertNull(directory.findOption("NOPE"));
+        verify(openCall, times(1)).getList(any(TargetSpec.class), eq(PATH), eq(Collections.emptyMap()), eq(VO_TYPE));
+    }
+
+    @Test
+    @DisplayName("T2 兼容性证明：旧三键+未知键 JSON 反序列化不炸（theme=null），新键正常映射")
+    void siteOptionVo_backwardCompatibleDeserialization() throws Exception {
+        com.fasterxml.jackson.databind.ObjectMapper mapper = new com.fasterxml.jackson.databind.ObjectMapper();
+        // 旧形态（CMS 未升级）+ 未来未知键：不得抛异常（@JsonIgnoreProperties 兜住）
+        SvcModels.SiteOptionVo legacy = mapper.readValue(
+                "{\"siteCode\":\"S1\",\"name\":\"站点一\",\"schId\":2,\"someFutureKey\":true}",
+                SvcModels.SiteOptionVo.class);
+        assertEquals("S1", legacy.getSiteCode());
+        assertNull(legacy.getTheme());
+        // 新形态：theme/themeParams 正常映射
+        SvcModels.SiteOptionVo fresh = mapper.readValue(
+                "{\"siteCode\":\"S2\",\"name\":\"站点二\",\"schId\":3,\"theme\":\"campus-glow\","
+                        + "\"themeParams\":{\"primary\":\"#0e8a5f\"}}",
+                SvcModels.SiteOptionVo.class);
+        assertEquals("campus-glow", fresh.getTheme());
+        assertEquals("#0e8a5f", fresh.getThemeParams().get("primary"));
+    }
+
     @Test
     @DisplayName("rootCauseBrief：ioError 包装层要透出最内层原因（区分\"对端没起\"与\"读超时\"）")
     void rootCauseBrief_exposesInnermostCause() {