Refactor provisioning/

[brentru]

src/provisioning/ is got muddled as we added features to v1/v2:

src/provisioning/
├── Config.h
├── ConfigJson.cpp
├── ConfigJson.h
├── littlefs
│   ├── WipperSnapper_LittleFS.cpp
│   └── WipperSnapper_LittleFS.h
├── sdcard
│   ├── ws_sdcard.cpp
│   └── ws_sdcard.h
└── tinyusb
    ├── fatfs
    │   ├── diskio.h
    │   ├── ff.c
    │   ├── ff.h
    │   └── ffconf.h
    ├── Wippersnapper_FS.cpp
    └── Wippersnapper_FS.h

What I'd like this to look like:

• create a filesystem/ dir
  • create a base filesystem class
  • create classes to handle FS-specific implementations for LittleFS and TinyUSB
• create a base class in provisioning/ instead to interact with the app-level provision() call and handle the high-level calls down to the filesystem class

extra, what to do with offline and sdcard:

• split out src/provisioning/sdcard/ to src/logger/sdcard to separate concerns
• figure out how sdlogger mode fits into provisioning call! Maybe it doesn't and we need a new mechanism/call for deciding which mode we are in (cloud or logger)! That is okay, we can create this