Fix parallel extraction wrong_password false positives, preserve session download counter across stop/resume

- Retry failed wrong_password archives serially after parallel extraction
  to recover from CRC mismatches caused by concurrent UnRAR I/O contention
- Stop resetting sessionDownloadedBytes on start/resume so the session
  total accurately reflects all bytes downloaded since app launch

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/main/download-manager.ts

@@ -3066,7 +3066,6 @@ export class DownloadManager extends EventEmitter {
     this.session.paused = false;
     this.session.runStartedAt = nowMs();
     this.session.totalDownloadedBytes = 0;
-    this.sessionDownloadedBytes = 0;
     this.session.summaryText = "";
     this.session.reconnectUntil = 0;
     this.session.reconnectReason = "";
@@ -3174,7 +3173,6 @@ export class DownloadManager extends EventEmitter {
     this.session.paused = false;
     this.session.runStartedAt = nowMs();
     this.session.totalDownloadedBytes = 0;
-    this.sessionDownloadedBytes = 0;
     this.session.summaryText = "";
     this.session.reconnectUntil = 0;
     this.session.reconnectReason = "";
@@ -3304,11 +3302,10 @@ export class DownloadManager extends EventEmitter {
 
     this.session.running = true;
     this.session.paused = false;
-    // By design: runStartedAt and totalDownloadedBytes reset on each start/resume so that
+    // Keep cumulative session bytes across stop/resume so the session total stays accurate.
-    // duration, average speed, and ETA are calculated relative to the current run, not cumulative.
+    // Only runStartedAt resets (for ETA/speed calculations relative to current run).
     this.session.runStartedAt = nowMs();
     this.session.totalDownloadedBytes = 0;
-    this.sessionDownloadedBytes = 0;
     this.session.summaryText = "";
     this.session.reconnectUntil = 0;
     this.session.reconnectReason = "";

src/main/extractor.ts

@@ -2742,6 +2742,35 @@ export async function extractPackageArchives(options: ExtractOptions): Promise<{
       passwordCandidates = frozenPasswords;
 
       if (abortError) throw new Error("aborted:extract");
+
+      // ── Retry failed wrong_password archives serially ──
+      // Parallel UnRAR processes writing to the same target directory can cause
+      // CRC mismatches that are misreported as "Incorrect password".
+      // If any archive succeeded (i.e. the password is known), retry the failed
+      // ones one-at-a-time to eliminate false positives from I/O contention.
+      if (failed > 0 && extracted > 0) {
+        const failedArchives = parallelQueue.filter((ap) => !extractedArchives.has(ap) && !resumeCompleted.has(archiveNameKey(path.basename(ap))));
+        if (failedArchives.length > 0) {
+          logger.info(`Serielle Wiederholung: ${failedArchives.length} fehlgeschlagene Archive werden einzeln wiederholt (mögliche Parallelitäts-Kollision)`);
+          let retryRecovered = 0;
+          for (const archivePath of failedArchives) {
+            if (options.signal?.aborted || noExtractorEncountered) break;
+            try {
+              // Reset failed count for this archive before retry
+              failed -= 1;
+              await extractSingleArchive(archivePath);
+              retryRecovered += 1;
+            } catch (retryError) {
+              const errText = String(retryError);
+              if (isExtractAbortError(errText)) throw retryError;
+              // extractSingleArchive already incremented failed and logged the error
+            }
+          }
+          if (retryRecovered > 0) {
+            logger.info(`Serielle Wiederholung: ${retryRecovered}/${failedArchives.length} Archive erfolgreich entpackt`);
+          }
+        }
+      }
     }
 
     if (noExtractorEncountered) {