Refactor freqman_db parsing (#1244)

* WIP freqman changes/memory perf/stash
* Split ui tone_key function out for testing.
* Add more tests and fix bugs.
* Use default max_entries in recond
* Set limit back to 90 for now

firmware/application/apps/ui_level.cpp

@@ -26,6 +26,7 @@
 #include "file.hpp"
 
 using namespace portapack;
+using namespace tonekey;
 using portapack::memory::map::backup_ram;
 
 namespace ui {