v1.7.1

🔧 Fixes

• AES-256 encrypted ZIP detection: 7-Zip-created encrypted ZIPs now correctly
  detected via CompressionMethod::AES + PasswordRequired error (the zip crate's
  encrypted() flag misses AES-256). Password prompt appears for these archives.
• Encrypted ZIP extraction: pre-scan loop now uses password when summing file
  sizes (was hitting encrypted entries first and erroring before extraction started).
• Progress watchdog: corrupt archives that cause the decoder to stall now show
  "Archive appears corrupt" after 15s instead of hanging forever.
• RAR4 support: confirmed working (tested with real RAR4 archive from unrar.rs test data).
• Compiler warnings: reduced from 27 to 15 via cargo fix.

---