feat(web): 地址栏驱动视图，刷新详情页不再回首页

- 新增 data/view.ts 与 useViewRoute：视图与地址双向同步，支持前进后退
- 条目地址带上所属分组，刷新 / 收藏后「返回」有确定落点
- 服务端只把 /c/** 回落到 index.html，其余路径仍返回 404
- 明细页返回按钮去掉左侧箭头图标

stash-web/src/useCatalog.ts

@@ -1,6 +1,5 @@
 import { useCallback, useEffect, useRef, useState } from 'react'
 import { fetchCatalog, subscribeCatalog } from './api'
-import { EMPTY_NAV, type NavModel } from './data/nav'
 import type { Category } from './data/types'
 
 export type CatalogStatus = 'loading' | 'ready' | 'error'
@@ -8,8 +7,6 @@ export type CatalogStatus = 'loading' | 'ready' | 'error'
 export type CatalogState = {
   status: CatalogStatus
   categories: Category[]
-  /** 侧栏导航；与分类同一次请求下发 */
-  nav: NavModel
   error: string | null
 }
 
@@ -32,7 +29,6 @@ export function useCatalog(): CatalogController {
   const [state, setState] = useState<CatalogState>({
     status: 'loading',
     categories: [],
-    nav: EMPTY_NAV,
     error: null,
   })
   const controllerRef = useRef<AbortController | null>(null)
@@ -54,7 +50,6 @@ export function useCatalog(): CatalogController {
           setState({
             status: 'ready',
             categories: catalog.categories,
-            nav: catalog.nav,
             error: null,
           })
         }
@@ -65,7 +60,6 @@ export function useCatalog(): CatalogController {
             // 已经有内容时只提示错误，不清空列表
             status: previous.categories.length > 0 ? 'ready' : 'error',
             categories: previous.categories,
-            nav: previous.nav,
             error: toErrorMessage(error),
           }))
         }