New LF-RFID app (#534)

* Hal lfrfid: add read timer pulse and period config fns
* New debug application for lfrfid subsystem
* New lfrfid: app, fix naming
* App lfrfid: assets
* Container view module
* App ibutton: remove unused header
* App lfrfid scenes
* App notification, add yield to blocking operations, add speaker volume control
* App lfrfid: reading key scene
* Assets: placeholder icon
* App lfrfid: reworked container view module
* App lfrfid: new scenes
* App lfrfid: write scene
* App lfrfid: write hid
* App lfrfid: emulate scene
* App lfrfid: save name scene
* App lfrfid: add missing file

applications/lfrfid/helpers/pulse-joiner.h

@@ -0,0 +1,36 @@
+#pragma once
+#include "stdint.h"
+
+class PulseJoiner {
+public:
+    /**
+     * @brief Push timer pulse. First negative pulse is ommited.
+     * 
+     * @param polarity pulse polarity: true = high2low, false = low2high
+     * @param period overall period time in timer clicks
+     * @param pulse pulse time in timer clicks
+     * 
+     * @return true - next pulse can and must be popped immediatly
+     */
+    bool push_pulse(bool polarity, uint16_t period, uint16_t pulse);
+
+    /**
+     * @brief Get the next timer pulse. Call only if push_pulse returns true.
+     * 
+     * @param period overall period time in timer clicks
+     * @param pulse pulse time in timer clicks
+     */
+    void pop_pulse(uint16_t* period, uint16_t* pulse);
+
+    PulseJoiner();
+
+private:
+    struct Pulse {
+        bool polarity;
+        uint16_t time;
+    };
+
+    uint8_t pulse_index = 0;
+    static const uint8_t pulse_max = 6;
+    Pulse pulses[pulse_max];
+};