Release v1.4.17 with security fixes, stability hardening and retry improvements

- Fix ZIP path traversal vulnerability (reject entries escaping target dir)
- Add single instance lock (prevent data corruption from multiple instances)
- Add unhandled exception/rejection handlers (prevent silent crashes)
- Fix mainWindow reference cleanup on close
- Add second-instance handler to focus existing window
- Fix claimTargetPath infinite loop (add 10k iteration bound)
- Add duplicate startItem guard (prevent concurrent downloads of same item)
- Clone session in getSnapshot to prevent live-reference mutation bugs
- Clear stateEmitTimer on clearAll to prevent dangling timer emissions
- Add extraction timeout safety (4h deadline with logging)
- Add dedicated unrestrict retry system with longer backoff for Mega-Debrid errors
- Add log rotation (10MB max, keeps one .old backup)
- Fix writeExtractResumeState missing mkdir (prevents crash on deleted dirs)
- Fix saveSessionAsync EXDEV cross-device rename with copy fallback

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

src/main/storage.ts

@@ -226,7 +226,16 @@ export async function saveSessionAsync(paths: StoragePaths, session: SessionStat
     const payload = JSON.stringify({ ...session, updatedAt: Date.now() });
     const tempPath = `${paths.sessionFile}.tmp`;
     await fsp.writeFile(tempPath, payload, "utf8");
-    await fsp.rename(tempPath, paths.sessionFile);
+    try {
+      await fsp.rename(tempPath, paths.sessionFile);
+    } catch (renameError: unknown) {
+      if ((renameError as NodeJS.ErrnoException).code === "EXDEV") {
+        await fsp.copyFile(tempPath, paths.sessionFile);
+        await fsp.rm(tempPath, { force: true }).catch(() => {});
+      } else {
+        throw renameError;
+      }
+    }
   } catch (error) {
     logger.error(`Async Session-Save fehlgeschlagen: ${String(error)}`);
   } finally {