Code improvements / Fix warnings

- Fix CodeQL warnings
- Port lots of improvements/fixes from PR #225
- replace 'array_hexstr' and '%*H' format by sdk function 'format_hex'
- Add 'noreturn' attribute in 'main.c'

src_plugins/erc721/erc721_plugin.c

@@ -32,7 +32,7 @@ static void handle_init_contract(void *parameters) {
     }
     uint8_t i;
     for (i = 0; i < SELECTORS_COUNT; i++) {
-        if (memcmp((uint8_t *) PIC(ERC721_SELECTORS[i]), msg->selector, SELECTOR_SIZE) == 0) {
+        if (memcmp(PIC(ERC721_SELECTORS[i]), msg->selector, SELECTOR_SIZE) == 0) {
             context->selectorIndex = i;
             break;
         }