feat(relation): 显示名可点 → 跳目标模块并过滤到该 _id(单行)

- VueAdmin: 记录 moduleKey→IRouteInfo(moduleRoutes)，加 routeForModule(判已注册+非子模块)
- FieldRelation.display: 目标可达时名字渲成链接，点击 router.push 到目标模块
  + ?filter={_id}，落成过滤到单条的列表(框架无详情页，单项查看即此形态)
- 子模块目标/无权限目标不可点(routeForModule 返回 undefined)

src/components/fields/FieldRelation.vue

@@ -1,7 +1,13 @@
 <template>
     <template v-if="mode === 'display'">
-        <template v-if="field.multiple">{{ displayNames.join('、') || '-' }}</template>
-        <template v-else>{{ displayName || '-' }}</template>
+        <template v-if="field.multiple">
+            <span v-if="!displayItems.length">-</span>
+            <template v-for="(it, i) in displayItems" :key="i"><a v-if="jumpable" class="rel-link" @click.stop="goto(it.id)">{{ it.name }}</a><span v-else>{{ it.name }}</span><span v-if="i < displayItems.length - 1">、</span></template>
+        </template>
+        <template v-else>
+            <a v-if="jumpable && modelValue != null" class="rel-link" @click.stop="goto(modelValue)">{{ displayName }}</a>
+            <span v-else>{{ displayName || '-' }}</span>
+        </template>
     </template>
     <el-select
         v-else-if="mode === 'filter'"
@@ -44,12 +50,22 @@ const displayName = computed(() => {
     if (id == null) return ''
     return dict.value[String(id)] ?? String(id)
 })
-const displayNames = computed(() =>
+const displayItems = computed(() =>
     (Array.isArray(props.modelValue) ? props.modelValue : [])
-        .map((id: any) => dict.value[String(id)] ?? String(id))
-        .filter(Boolean)
+        .filter((id: any) => id != null)
+        .map((id: any) => ({ id, name: dict.value[String(id)] ?? String(id) }))
 )
 
+// 单项查看跳转：目标模块可达(已注册路由)且非子模块时，名字可点 → 跳目标模块并过滤到该 _id(单行)
+const jumpable = computed(() =>
+    props.mode === 'display' && !!props.field.relation && !!vueAdmin.routeForModule(props.field.relation.moduleKey)
+)
+function goto(id: any) {
+    const r = props.field.relation && vueAdmin.routeForModule(props.field.relation.moduleKey)
+    if (!r || id == null) return
+    vueAdmin.router.push({ name: r.name, query: { filter: JSON.stringify({ _id: String(id) }) } })
+}
+
 /** 统一转为字符串值，解决 ObjectId 与 el-select 的匹配问题 */
 const stringValue = computed(() => {
     // filter 模式强制 multiple，始终返回数组
@@ -105,3 +121,13 @@ onMounted(async () => {
     }
 })
 </script>
+
+<style scoped>
+.rel-link {
+    color: var(--el-color-primary);
+    cursor: pointer;
+}
+.rel-link:hover {
+    text-decoration: underline;
+}
+</style>