Downloads fail on Linux containers when filenames contain square
brackets or multiple consecutive spaces. On Linux, .NET's
Path.GetInvalidFileNameChars() only returns NUL and '/', so characters
like [ ] { } that cause issues with shell globbing, URI handling, and
various download clients pass through the existing filter unchanged.
Add FilenameSanitizer that:
- Strips square brackets, curly braces, and control characters
- Collapses multiple consecutive spaces into one
- Trims leading and trailing whitespace
- Preserves parentheses and all other characters
Apply sanitization at filesystem boundaries: DownloadHelper (where the
Real-Debrid filename is turned into a local path), UnpackClient,
Torrent delete / RunOnTorrentComplete, and the qBittorrent / SABnzbd
status paths that *arr reads back. Aria2c and DownloadStation also
sanitize their remote output paths so they match the sanitized local
filePath. Symlink's rclone-mount lookup still uses the original name
since that has to match the real file in the mount.
Add a SanitizeFilenames toggle in DbSettings (default on) so users
can disable the behaviour if they need the exact Real-Debrid name.
The previous fix compared subPath directly against the sanitized torrent
name, which fails when RdName contains characters removed by
RemoveInvalidPathChars (e.g. ':' on Windows). Extract and normalize the
first component of subPath before comparing so both sides go through the
same sanitization. Add tests covering the duplicate-prefix stripping case.
torrent.Files[].Path already includes the torrent name as its first
component (e.g. "Hijack/Saison 1/file.mkv"), but GetDownloadPath was
also initialising torrentPath with torrent.RdName, causing the name
to appear twice (e.g. "Hijack/Hijack/Saison 1"). Strip the torrent
name prefix from subPath before combining so the resolved path matches
the actual rclone mount layout.
