🐛 fix(vscode): 改动 tab 默认统一视图并保留阅读位置

vscode/src/panel/handlers/prFiles.ts

@@ -19,6 +19,7 @@ import { getPullRequest, getRawFile, listPullRequestFiles } from '../../gitea/ap
 import { readStateJsonComment } from '../../gitea/stateJson'
 import { readFileSummaries, readSummarySession, writeFileSummary, writeSummarySession } from '../../sessions/prFileSummaryStore'
 import { readConfirmedSigs, writeConfirmedSigs } from '../../sessions/prReviewStore'
+import { parsePrDiffMode, type PrDiffMode } from '../../cc/prDiffMode'
 import { makeNonce } from '../KanbanPanel'
 
 /**
@@ -351,3 +352,22 @@ export async function handleGeneratePrFileSummary(
     })
   }
 }
+
+const PR_DIFF_MODE_KEY = 'prDiffMode'
+
+/** 读 workspace 级 diff 模式（缺省 unified），回推 webview。 */
+export function handleGetPrDiffMode(panel: KanbanWebviewPanel): void {
+  const stored = panel.context.workspaceState.get<unknown>(PR_DIFF_MODE_KEY)
+  const mode = parsePrDiffMode(stored)
+  panel.postMessage({ type: 'pr-diff-mode/show', mode })
+}
+
+/** 写 workspace 级 diff 模式；非法值按 unified 落盘。 */
+export async function handleSetPrDiffMode(
+  panel: KanbanWebviewPanel,
+  mode: unknown,
+): Promise<void> {
+  const next: PrDiffMode = parsePrDiffMode(mode)
+  await panel.context.workspaceState.update(PR_DIFF_MODE_KEY, next)
+}
+