feat: advance local-first conflict and search indexing

- 补齐本地 markdown 冲突处理与合并写回路径\n- 增加本地搜索索引路由、刷新与 browser smoke\n- 同步更新 current-priority checklist 的阶段进度

scripts/task451-local-markdown-conflict-resolution-ui-smoke.js

@@ -113,9 +113,13 @@ async function run() {
   const root = fs.mkdtempSync(path.join(os.tmpdir(), "mnote-local-conflict-ui-"));
   const acceptFile = "accept-disk.md";
   const keepFile = "keep-current.md";
+  const mergeFile = "merge-result.md";
+  const agentFile = "agent-conflict.md";
   writeWorkspaceManifest(root, "user_real");
   fs.writeFileSync(path.join(root, acceptFile), markdown("Accept Disk", ["initial accept"]), "utf8");
   fs.writeFileSync(path.join(root, keepFile), markdown("Keep Current", ["initial keep"]), "utf8");
+  fs.writeFileSync(path.join(root, mergeFile), markdown("Merge Result", ["initial merge"]), "utf8");
+  fs.writeFileSync(path.join(root, agentFile), markdown("Agent Conflict", ["initial agent"]), "utf8");
 
   const browser = await chromium.launch({
     headless: true,
@@ -189,6 +193,57 @@ async function run() {
     assert(!keepContent.includes(diskKeepToken), "保留当前版本后磁盘版本内容不应覆盖当前编辑器内容");
     steps.push({ label: "keep-current", ok: true });
 
+    await openDocument(page, root, mergeFile);
+    await waitForEditorText(page, "initial merge");
+    const localMergeToken = `local-merge-${Date.now()}`;
+    const diskMergeToken = `disk-merge-${Date.now()}`;
+    const mergedToken = `merged-merge-${Date.now()}`;
+    await typeDirtyText(page, ` ${localMergeToken}`);
+    fs.writeFileSync(path.join(root, mergeFile), markdown("Merge Result", ["initial merge", diskMergeToken]), "utf8");
+    await waitForEditorStatus(page, "external-change-conflict");
+    await page.locator('[data-testid="mnote-editor-conflict-panel"]').waitFor({ state: "visible", timeout: UI_TIMEOUT_MS });
+    await page.locator('[data-testid="mnote-conflict-open-diff"]').click({ timeout: UI_TIMEOUT_MS });
+    await page.locator('[data-testid="mnote-conflict-diff-panel"]').waitFor({ state: "visible", timeout: UI_TIMEOUT_MS });
+    await page.locator('[data-testid="mnote-conflict-merge-text"]').fill(`initial merge\n${localMergeToken}\n${diskMergeToken}\n${mergedToken}`);
+    await page.locator('[data-testid="mnote-conflict-merge-save"]').click({ timeout: UI_TIMEOUT_MS });
+    await waitForFileText(path.join(root, mergeFile), mergedToken);
+    const mergeContent = fs.readFileSync(path.join(root, mergeFile), "utf8");
+    assert(mergeContent.includes(localMergeToken), "合并结果应保留当前编辑器内容");
+    assert(mergeContent.includes(diskMergeToken), "合并结果应保留磁盘内容");
+    assert(mergeContent.includes(mergedToken), "合并结果应写入合并后的新内容");
+    steps.push({ label: "merge-save", ok: true });
+
+    await openDocument(page, root, agentFile);
+    await waitForEditorText(page, "initial agent");
+    const localAgentToken = `local-agent-${Date.now()}`;
+    const diskAgentToken = `disk-agent-${Date.now()}`;
+    const agentRunId = `run-agent-conflict-${Date.now()}`;
+    await typeDirtyText(page, ` ${localAgentToken}`);
+    fs.writeFileSync(path.join(root, agentFile), markdown("Agent Conflict", ["initial agent", diskAgentToken]), "utf8");
+    await page.evaluate(({ documentId, runId }) => {
+      window.dispatchEvent(new CustomEvent("mnote:page-ai-tool-write-completed", {
+        detail: {
+          toolName: "agent.changed_files",
+          normalizedToolName: "agent.changed_files",
+          documentId,
+          runId,
+          traceId: `trace-${runId}`,
+          toolCallId: `${runId}:agent.changed_files`,
+        },
+      }));
+    }, { documentId: localMdDocumentId(agentFile), runId: agentRunId });
+    await waitForEditorStatus(page, "external-change-conflict");
+    await page.locator('[data-testid="mnote-editor-conflict-panel"]').waitFor({ state: "visible", timeout: UI_TIMEOUT_MS });
+    await page.waitForFunction(
+      (expected) => {
+        const panel = document.querySelector('[data-testid="mnote-editor-conflict-panel"]');
+        return (panel?.textContent || "").includes(expected);
+      },
+      `agent run ${agentRunId}`,
+      { timeout: UI_TIMEOUT_MS },
+    );
+    steps.push({ label: "agent-conflict-source", ok: true });
+
     const result = { ok: true, baseUrl: BASE_URL, root, steps };
     fs.writeFileSync(RESULT_PATH, `${JSON.stringify(result, null, 2)}\n`, "utf8");
     console.log(`task451 local markdown conflict resolution UI smoke passed: ${RESULT_PATH}`);