card storage: make more robust, handle cards that are already seen, implement in nfc read

src/bin/main.rs

@@ -22,6 +22,7 @@ use creaturedex::network::wifi::setup_wifi;
 use creaturedex::storage::cardstore::CardStore;
 use creaturedex::storage::store::Store;
 use embassy_executor::Spawner;
+use embassy_time::Instant;
 use embedded_graphics::pixelcolor::BinaryColor;
 use embedded_graphics::{
     mono_font::{MonoTextStyle, ascii::FONT_6X10},
@@ -29,6 +30,8 @@ use embedded_graphics::{
     text::Text,
 };
 use embedded_hal_bus::i2c::AtomicDevice;
+use embedded_hal_bus::util::AtomicCell;
+use esp_hal::Blocking;
 use esp_hal::clock::CpuClock;
 use esp_hal::gpio::{Input, InputConfig, Pull};
 use esp_hal::timer::timg::TimerGroup;