Fix extraction speed: I/O priority only in hybrid mode, more threads

- setWindowsBackgroundIO (Very Low I/O) now only applied in hybrid mode,
  not for all extractions (was causing massive slowdown)
- Hybrid threads changed from -mt1 to half CPU count (e.g. -mt4 on 8-core)
- Move retry count (R9, R22 etc.) from status text to tooltip only

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

package.json

@@ -1,6 +1,6 @@
 {
   "name": "real-debrid-downloader",
-  "version": "1.5.40",
+  "version": "1.5.41",
   "description": "Real-Debrid Downloader Desktop (Electron + React + TypeScript)",
   "main": "build/main/main/main.js",
   "author": "Sucukdeluxe",