Support Webdav in the web workflow

[Neradoc]

It would be nice to support some native clients in the web workflow.
Since we already have a web server, we could add (some of) the Webdav extensions to it.
That would allow accessing the files with a file manager application like Cyberduck, even mount as a drive on the computer (and run circup, why not). This in turn allows editing the code with our editor/IDE of choice, some of them might even directly support webdav.

It might not be necessary to support all of the commands, the nginx webdav module seems to only support PUT, DELETE, MKCOL, COPY, and MOVE for example.
The question is, what clients are there, and what do they need to be supported ?
And how much space will that take ?

Here is a list from wikipedia:

• CloudMounter from Eltima Software
• Git supports writing to HTTP remotes
• Linux via GVfs, including GNOME Files and via KIO, including Konqueror and Dolphin
• macOS, including native support for CalDAV and CardDAV, the design of which is based on WebDAV
• Microsoft Windows and Microsoft Office, including native support in Explorer, via the WebDAV Redirector[22]
• NetDrive from Bdrive, Inc.
• WebDrive from South River Technologies
• WinSCP from Martin Přikryl

[IrregularShed]

I dreamt about this last night (exciting, huh?). It would a huge quality of life improvement for non-native USB devices. This led me to ponder FUSE on Linux/Mac and WinFsp on Windows, but the much more native WebDAV would be preferable for portability between systems.

[vvuk]

From a quick glance -- this should be fairly straightforward to implement, given that the web workflow is all implemented in straight C (i.e. there is no "web server" framework, it's all directly implemented). The only complication is probably PROPFIND -- DAV PROPFIND works with XML documents, including proper namespace definitions and such, meaning that at least a very lightweight XML namespace aware xml parser would need to be present. Something like yxml might be a good fit for that.