fmt: fix and prevent future use of unsupported format spec "zu"

### gitlab/test.yml
@@ -17,6 +17,7 @@ test_format:
   dependencies: []
   script:
     - pushd /opt/esp/idf && . ./export.sh && popd
+    - if git grep -I '%zu' main/ libjade/; then echo 'unsupported format spec "zu"'; echo exit 1; fi
     - ./format.sh
     - idf.py reconfigure
     - git diff --exit-code

### libjade/selfcheck/cbor.c
@@ -50,7 +50,7 @@ static bool test_parser_recursion_limit(void)
     enum { MIN_DEPTH = CBOR_PARSER_MAX_RECURSIONS - 1, MAX_DEPTH = CBOR_PARSER_MAX_RECURSIONS + 1 };
     uint8_t cbor[MAX_DEPTH + 1];
 
-    for (size_t depth = MIN_DEPTH; depth <= MAX_DEPTH; ++depth) {
+    for (unsigned int depth = MIN_DEPTH; depth <= MAX_DEPTH; ++depth) {
         // A single-item array at each level, terminated by a null leaf:
         // [[[...[null]...]]]
         memset(cbor, CborArrayType | 1, depth); // one element arrays
@@ -65,9 +65,9 @@ static bool test_parser_recursion_limit(void)
         const CborError expected_err = depth <= CBOR_PARSER_MAX_RECURSIONS ? CborNoError : CborErrorNestingTooDeep;
         const CborError err = cbor_value_validate_basic(&root);
         const char* err_text = err == CborNoError ? "ok" : cbor_error_string(err);
-        JADE_LOGD("Validating CBOR with nesting depth %zu: %s", depth, err_text);
+        JADE_LOGD("Validating CBOR with nesting depth %u: %s", depth, err_text);
         if (err != expected_err) {
-            JADE_LOGE("Failed CBOR validation case with nesting depth %zu", depth);
+            JADE_LOGE("Failed CBOR validation case with nesting depth %u", depth);
             return false;
         }
     }

### main/otpauth.c
@@ -411,7 +411,7 @@ static bool decode_otp_parameters_fn(pb_istream_t* stream, const pb_field_t* fie
         }
     }
     if (i == ctx->uris_out_len) {
-        JADE_LOGE("Too many OTP records in migration data, max supported is %zu", ctx->uris_out_len);
+        JADE_LOGE("Too many OTP records in migration data, max supported is %u", (unsigned int)ctx->uris_out_len);
         return false;
     }
 

### main/process/mnemonic.c
@@ -324,7 +324,7 @@ static bool display_confirm_mnemonic(const size_t nwords, char* mnemonic, const
             gui_view_node_t* textbox = NULL;
             gui_activity_t* const confirm_act
                 = make_confirm_mnemonic_word_activity(&textbox, i, offset_word_to_confirm, mnemonic, word_offs, nwords);
-            JADE_LOGD("selected = %zu", selected);
+            JADE_LOGD("selected = %u", (unsigned int)selected);
 
             // Pick some other words from the mnemonic as options, but avoid
             // the words currently displayed on screen (neighbouring words).
@@ -435,7 +435,7 @@ static void enable_relevant_chars(const bool is_mnemonic, const char* word, cons
     JADE_ASSERT(act && backspace && enter && btns && btns_len == 26);
     JADE_ASSERT(backspace->activity == act && enter->activity == act);
 
-    JADE_LOGD("word = %s, word_len = %zu", word, word_len);
+    JADE_LOGD("word = %s, word_len = %u", word, (unsigned int)word_len);
 
     // Enable enter if a) not entering a mnemonic, and b) not part-way through entering a word
     // Enable backspace in all cases.
@@ -711,7 +711,8 @@ static wordlist_word_result_t select_wordlist_word(const bool is_mnemonic, const
         if (possible_words <= NUM_WORDS_SELECT) {
             // 'Small' number of words - allow user to select from these words
             char choose_word_title[16]; // sufficient
-            const int ret = snprintf(choose_word_title, sizeof(choose_word_title), "Select word %zu", word_index + 1);
+            const int ret = snprintf(
+                choose_word_title, sizeof(choose_word_title), "Select word %u", (unsigned int)(word_index + 1));
             JADE_ASSERT(ret > 0 && ret < sizeof(choose_word_title));
             gui_update_text(ui->label, choose_word_title);
 
@@ -853,7 +854,8 @@ static wordlist_word_result_t select_resolved_word_number(const size_t word_inde
     JADE_ASSERT(word && choose_word_activity && label && text_selection);
 
     char confirm_word_title[16]; // sufficient
-    const int ret = snprintf(confirm_word_title, sizeof(confirm_word_title), "Confirm word %zu", word_index + 1);
+    const int ret
+        = snprintf(confirm_word_title, sizeof(confirm_word_title), "Confirm word %u", (unsigned int)(word_index + 1));
     JADE_ASSERT(ret > 0 && ret < sizeof(confirm_word_title));
     gui_update_text(label, confirm_word_title);
 
@@ -939,7 +941,8 @@ static size_t get_wordlist_words(
         // Reset default title for next word when entering mnemonic phrase
         if (is_mnemonic) {
             char enter_word_title[16];
-            const int ret = snprintf(enter_word_title, sizeof(enter_word_title), "Insert word %zu", word_index + 1);
+            const int ret = snprintf(
+                enter_word_title, sizeof(enter_word_title), "Insert word %u", (unsigned int)(word_index + 1));
             JADE_ASSERT(ret > 0 && ret < sizeof(enter_word_title));
             gui_update_text(ui.titletext, enter_word_title);
         }
@@ -1039,7 +1042,8 @@ static size_t get_word_number_words(
         JADE_ASSERT(!wordlist_words[word_index]);
 
         char title[24];
-        const int ret = snprintf(title, sizeof(title), "Word %zu/%zu", word_index + 1, nwords);
+        const int ret
+            = snprintf(title, sizeof(title), "Word %u/%u", (unsigned int)(word_index + 1), (unsigned int)nwords);
         JADE_ASSERT(ret > 0 && ret < sizeof(title));
 
         const char* word = NULL;
@@ -1053,7 +1057,8 @@ static size_t get_word_number_words(
                 = calculate_valid_final_words(wordlist_words, word_index, nwords, final_words);
 
             char enter_word_title[16];
-            const int ret = snprintf(enter_word_title, sizeof(enter_word_title), "Insert word %zu", word_index + 1);
+            const int ret = snprintf(
+                enter_word_title, sizeof(enter_word_title), "Insert word %u", (unsigned int)(word_index + 1));
             JADE_ASSERT(ret > 0 && ret < sizeof(enter_word_title));
             gui_update_text(calc_ui.titletext, enter_word_title);
 
@@ -1391,7 +1396,7 @@ static bool mnemonic_qr(char* mnemonic, const size_t mnemonic_len)
     }
 
     if (qr_data.len >= mnemonic_len) {
-        JADE_LOGW("String data from qr unexpectedly long - ignored: %zu", qr_data.len);
+        JADE_LOGW("String data from qr unexpectedly long - ignored: %u", (unsigned int)qr_data.len);
         goto cleanup;
     }
 
@@ -1458,7 +1463,7 @@ void get_passphrase(char* passphrase, const size_t passphrase_len)
         // Passphrase made up only of bip39 wordlist words
         const size_t nwords
             = get_wordlist_words(WORDLIST_PASSPHRASE, WORDLIST_PASSPHRASE_MAX_WORDS, passphrase, passphrase_len);
-        JADE_LOGI("%zu wordlist words used for passphrase", nwords);
+        JADE_LOGI("%u wordlist words used for passphrase", (unsigned int)nwords);
     } else {
         // Free-text passphrase
         get_freetext_passphrase(passphrase, passphrase_len);

### main/process/sign_utils.c
@@ -137,7 +137,8 @@ static bool rpc_get_asset_summary(jade_process_t* process, const char* field, co
     }
 
     if (num_array_items > max_items) {
-        JADE_LOGE("Too many asset summary records in message: %zu (max %zu)", num_array_items, max_items);
+        JADE_LOGE("Too many asset summary records in message: %u (max %u)", (unsigned int)num_array_items,
+            (unsigned int)max_items);
         return false;
     }