fix: memory leak hunting and reconnecting on data error

electron/db/database.ts

@@ -41,7 +41,14 @@ const RETRYABLE_SAVE_ERROR_CODES = new Set([
   'EBUSY'
 ]);
 
-let saveQueue: Promise<void> = Promise.resolve();
+interface PendingSaveWaiter {
+  reject: (error: unknown) => void;
+  resolve: () => void;
+}
+
+let pendingSaveSnapshot: Buffer | null = null;
+let pendingSaveWaiters: PendingSaveWaiter[] = [];
+let saveInProgress = false;
 
 function wait(ms: number): Promise<void> {
   return new Promise((resolve) => setTimeout(resolve, ms));
@@ -146,16 +153,51 @@ async function writeDatabaseSnapshot(snapshot: Buffer): Promise<void> {
   }
 }
 
+function settleSaveWaiters(waiters: PendingSaveWaiter[], error?: unknown): void {
+  for (const waiter of waiters) {
+    if (error === undefined) {
+      waiter.resolve();
+    } else {
+      waiter.reject(error);
+    }
+  }
+}
+
+async function drainDatabaseSaveQueue(): Promise<void> {
+  if (saveInProgress) {
+    return;
+  }
+
+  saveInProgress = true;
+
+  try {
+    while (pendingSaveSnapshot) {
+      const snapshot = pendingSaveSnapshot;
+      const waiters = pendingSaveWaiters;
+
+      pendingSaveSnapshot = null;
+      pendingSaveWaiters = [];
+
+      try {
+        await writeDatabaseSnapshot(snapshot);
+        settleSaveWaiters(waiters);
+      } catch (error) {
+        settleSaveWaiters(waiters, error);
+      }
+    }
+  } finally {
+    saveInProgress = false;
+  }
+}
+
 async function atomicSave(data: Uint8Array): Promise<void> {
   const snapshot = Buffer.from(data);
-  const saveTask = saveQueue.then(
-    () => writeDatabaseSnapshot(snapshot),
-    () => writeDatabaseSnapshot(snapshot)
-  );
 
-  saveQueue = saveTask.catch(() => {});
-
-  return saveTask;
+  return new Promise<void>((resolve, reject) => {
+    pendingSaveSnapshot = snapshot;
+    pendingSaveWaiters.push({ resolve, reject });
+    void drainDatabaseSaveQueue();
+  });
 }
 
 export async function initializeDatabase(): Promise<void> {