A file system provider

[DannyAlas]

An efficient file system provider. It uses multiple processes to scan through many files efficiently and provides a centralized place to implement file system-related tasks. Based off #187 - explanations 1, 2

Implements a cross-platform method for acquiring system unique file IDs - fixing/minimizing relinking issues.

Implements file system watching using the Qt provided QFileSystemWatcher. As an alternative to #125 (still requires implementation into Library class)

[BilliAlpha]

It would be interesting to provide abstraction and create a generic file provider interface (with a default implementation per OS filesystem) so that we could later add support for other file systems (be it on the network, encrypted or really anything). It would allow support for S3, FTP, SSHFS, GPG encrypted files etc ...

[seakrueger]

Just wanted to bump this and check if this is still being worked on. I know this is a very old PR and probably has diverged from main a lot, but wanted to check on the current state of this? Thanks!