fix: 修复 chat 视图无法滚动 + SSE 事件重复消费

- scrollResultToLatest 守卫条件兼容 chat 视图
- shortNovel.js 添加 chunkProcessed 标志位避免 H5 双重消费

mini-program/src/pages/main/ScriptView.vue

@@ -866,7 +866,7 @@ const keepGenerationAtBottom = () => {
 }
 
 const scrollResultToLatest = () => {
-  if (viewState.value !== 'result') return
+  if (viewState.value !== 'result' && viewState.value !== 'chat') return
   nextTick(() => {
     measureResultViewport()
     pushResultScrollCommand(1000000)

mini-program/src/services/shortNovel.js

@@ -14,6 +14,7 @@ import { getApiBaseUrl, getAuthHeader } from './request.js'
  * @returns {Object} uni.request 任务对象（用于 abort）
  */
 export const startNovelStream = ({ query, onEvent, onError }) => {
+  let chunkProcessed = false
   const task = uni.request({
     url: `${getApiBaseUrl()}/shortNovel/stream`,
     method: 'POST',
@@ -30,7 +31,8 @@ export const startNovelStream = ({ query, onEvent, onError }) => {
         onError?.(res.data?.message || '请求失败')
         return
       }
-      if (typeof res.data === 'string' && res.data) {
+      // 仅在 chunk 未处理时才处理完整 data（避免 H5 双重消费）
+      if (!chunkProcessed && typeof res.data === 'string' && res.data) {
         consumeSseText(res.data, onEvent, onError)
       }
     },
@@ -40,6 +42,7 @@ export const startNovelStream = ({ query, onEvent, onError }) => {
   })
 
   task?.onChunkReceived?.((res) => {
+    chunkProcessed = true
     try {
       const text = decodeChunk(res.data)
       consumeSseText(text, onEvent, onError)
@@ -62,6 +65,7 @@ export const startNovelStream = ({ query, onEvent, onError }) => {
  * @returns {Object} uni.request 任务对象
  */
 export const followupStream = ({ sessionId, action, payload, onEvent, onError }) => {
+  let chunkProcessed = false
   const task = uni.request({
     url: `${getApiBaseUrl()}/shortNovel/followup`,
     method: 'POST',
@@ -78,7 +82,7 @@ export const followupStream = ({ sessionId, action, payload, onEvent, onError })
         onError?.(res.data?.message || '请求失败')
         return
       }
-      if (typeof res.data === 'string' && res.data) {
+      if (!chunkProcessed && typeof res.data === 'string' && res.data) {
         consumeSseText(res.data, onEvent, onError)
       }
     },
@@ -88,6 +92,7 @@ export const followupStream = ({ sessionId, action, payload, onEvent, onError })
   })
 
   task?.onChunkReceived?.((res) => {
+    chunkProcessed = true
     try {
       const text = decodeChunk(res.data)
       consumeSseText(text, onEvent, onError)