[FL-2415] Storage: blocking file open (#1078)

* Storage: correct replacement for "/any" path in path holder
* Unit tests: storage, blocking file open test
* File stream: error getter
* Storage: common copy and common remove now executes in external thread
* Filesystems: got rid of unused functions
* Storage: untangle dependencies, ram-frendly filesystem api
* iButton: context assertions
* Storage: pubsub messages
* Storage: wait for the file to close if it was open
* Storage: fix folder copying
* Storage: unit test
* Storage: pubsub documentation
* Fix merge error
* Fix memleak in storage test
* Storage: remove unused define

Co-authored-by: あく <alleteam@gmail.com>

applications/ibutton/scene/ibutton_scene_emulate.cpp

@@ -3,6 +3,7 @@
 #include <dolphin/dolphin.h>
 
 static void emulate_callback(void* context, bool emulated) {
+    furi_assert(context);
     if(emulated) {
         iButtonApp* app = static_cast<iButtonApp*>(context);
         iButtonEvent event = {.type = iButtonEvent::Type::EventTypeWorkerEmulated};