perf: diagnoistics improvements

electron/diagnostics/high-memory-alert.store.ts

@@ -0,0 +1,57 @@
+import * as fsp from 'fs/promises';
+import * as path from 'path';
+
+export interface HighMemoryAlertRecord {
+  logFilePath: string;
+  detectedAt: number;
+  peakWorkingSetKb: number;
+  sessionId: string;
+}
+
+export function resolveHighMemoryAlertPath(userDataPath: string): string {
+  return path.join(userDataPath, 'diagnostics', 'high-memory-pending.json');
+}
+
+export async function readHighMemoryAlert(userDataPath: string): Promise<HighMemoryAlertRecord | null> {
+  try {
+    const raw = await fsp.readFile(resolveHighMemoryAlertPath(userDataPath), 'utf8');
+    const parsed = JSON.parse(raw) as Partial<HighMemoryAlertRecord>;
+
+    if (
+      typeof parsed.logFilePath !== 'string'
+      || !parsed.logFilePath.trim()
+      || typeof parsed.detectedAt !== 'number'
+      || typeof parsed.peakWorkingSetKb !== 'number'
+      || typeof parsed.sessionId !== 'string'
+    ) {
+      return null;
+    }
+
+    return {
+      logFilePath: parsed.logFilePath,
+      detectedAt: parsed.detectedAt,
+      peakWorkingSetKb: parsed.peakWorkingSetKb,
+      sessionId: parsed.sessionId
+    };
+  } catch {
+    return null;
+  }
+}
+
+export async function writeHighMemoryAlert(
+  userDataPath: string,
+  record: HighMemoryAlertRecord
+): Promise<void> {
+  const filePath = resolveHighMemoryAlertPath(userDataPath);
+
+  await fsp.mkdir(path.dirname(filePath), { recursive: true });
+  await fsp.writeFile(filePath, `${JSON.stringify(record, null, 2)}\n`, 'utf8');
+}
+
+export async function clearHighMemoryAlert(userDataPath: string): Promise<void> {
+  try {
+    await fsp.unlink(resolveHighMemoryAlertPath(userDataPath));
+  } catch {
+    // Missing pending alert is fine.
+  }
+}