Document Filesystem errors

[beruic]

Feature Request

Plugin

@capacitor/filesystem

Description

There is no documentation of errors on rejection of file operations in the Filesystem plugin.

This goes for both https://capacitorjs.com/docs/apis/filesystem or https://capacitorjs.com/docs/v3/apis/filesystem

Platform(s)

All

Preferred Solution

Documentation should be added.

Alternatives

Additional Context

[beruic]

This is also reported at ionic-team/capacitor-site#264