fix: 处理 Copilot 二轮 review 的 10 条评论

- BrowserView: 即使 host 在白名单，GUI 自身 origin 永不给 allow-same-origin（裸 host 条目覆盖所有端口时可提权）
- intercept: revealInExplorer 相对路径经 resolveSidebarPath 解析后再 revealPaths（交付物路径是相对的）
- intercept: ctx.betterSidebar 改为 ctx.get（#357 纤维链读取约定）
- FileTree/EditorHost/TreePanel/tabs: 把 revealed 贯通到树行渲染 + 高亮类 + scrollIntoView（此前高亮永不渲染）
- state.revealPaths: 重建祖先目录时保留前导分隔符（POSIX/UNC 此前目录永远折叠）
- state.schedulePersist: 仅活动会话写入全局宽度（targeted open 不再用非活动会话的过期宽度覆盖拖拽值）
- browser.probe: GET 回退显式取消 body（否则流式/大响应挂住 socket）
- terminal-font: leading generic 前只放 symbols-only 字体；fully-patched 放 generic 后（避免 hijack 度量字体）
- sidebar.module.css: 恢复拖拽反馈（#130 的 silent resize 与 PR 描述冲突，取 HEAD）
- Sidebar: 剩余 4 处 ctx.betterSidebar 改 ctx.get
- tests: 补 revealPaths/iframeSandboxFor/terminal-font 回归测试 + EditorHost/FileTree 测试补 revealed prop

src/client/intercept.tsx

@@ -46,7 +46,12 @@ export function revealInExplorer(
 ): void {
   const summary = ctx.sessions.list.getSnapshot().byId[sessionId]
   const cwd = summary?.cwd
-  const targets = files.length > 0 ? files : cwd === undefined ? [] : [cwd]
+  // Deliverables report paths as-is (often relative to the session cwd), but
+  // the explorer tree and revealPaths work on absolute paths — resolve every
+  // target so the ancestors expand and the row actually matches.
+  const targets = files.length > 0
+    ? files.map(path => resolveSidebarPath(cwd, path))
+    : cwd === undefined ? [] : [cwd]
   store.reduce(state => revealPaths(state, cwd, targets))
   // A type-only open never auto-expands the panel (only content opens do,
   // see service.openTab) — so a reveal opens the panel itself when it is
@@ -58,8 +63,10 @@ export function revealInExplorer(
   // touched.
   store.reduce(s => ({ ...s, activePane: firstLeaf(s.splits).id }))
   // Focus the single-instance editor home tab (the files window) where the
-  // reveal highlight renders.
-  ctx.betterSidebar?.openTab({ type: 'editor', title: t('files') })
+  // reveal highlight renders. Read via ctx.get like every other internal
+  // consumer (#357): the provider is not on this fiber chain, so a direct
+  // ctx.betterSidebar read can throw before optional chaining applies.
+  ctx.get('betterSidebar')?.openTab({ type: 'editor', title: t('files') })
 }
 
 /** The intercepted produced-files row (visual twin of the deliverables chips). */