Better filename sanitization

[hannaeko]

Using sanitize.Name can end up with file conflict when there are / in titles. Example include titles ending with (1/2) and (2/2) both being sanitize to 2). This changes it for BaseName which replace slashes with dashes instead of keeping only the last segment.

[akhilrex]

Give me some time. Let me test this across multiple scenarios and then merge this.