handshake-capture-c6: SPI bus lock, SD v1.0.2 diagnostics, MUST_DO review

- SPI_Bus_Lock: serialize LCD + SD on shared SPI; pause display during SD
- SD_Init after WiFi scan; SD_IsReady gating; serial [SD]/[CAP] diagnostics
- MUST_DO_IMPROVEMENTS.md full firmware review backlog; README link
- Bump HANDSHAKE_FIRMWARE_VERSION to 1.0.2 (header)

Made-with: Cursor

handshake-capture-c6/WiFi_Scanner.cpp

@@ -10,9 +10,17 @@ void WiFiScanner_Refresh(void) {
   scanNetworksSortedByRSSI();
 
   int count = 0;
+  int captureable = 0;
+  int offband_secure = 0;
   for (int i = 0; i < MAX_NETWORKS; i++) {
     if (networks[i].ssid.isEmpty()) break;
     count++;
+    if (isCaptureable(i)) {
+      captureable++;
+    } else if (isSupportedCaptureAuth(networks[i].encryption) &&
+               !isSupportedCaptureChannel(networks[i].ch)) {
+      offband_secure++;
+    }
   }
 
   if (count <= 0) {
@@ -22,20 +30,33 @@ void WiFiScanner_Refresh(void) {
   }
 
   static char status_text[64];
-  snprintf(status_text, sizeof(status_text), "%d networks", count);
+  if (offband_secure > 0) {
+    snprintf(status_text, sizeof(status_text), "%d nets, %d tgt, %d off-band",
+             count, captureable, offband_secure);
+  } else {
+    snprintf(status_text, sizeof(status_text), "%d nets, %d tgt", count, captureable);
+  }
   Ui_SetWifiStatus(status_text);
 
   for (int i = 0; i < count; i++) {
     char line[48];
-    snprintf(line, sizeof(line), "%02d. %s ch%d",
+    const char* suffix = "";
+    if (isSupportedCaptureAuth(networks[i].encryption) &&
+        !isSupportedCaptureChannel(networks[i].ch)) {
+      suffix = " 5G+";
+    }
+    snprintf(line, sizeof(line), "%02d. %s ch%d%s",
              i + 1,
              networks[i].ssid.c_str(),
-             networks[i].ch);
+             networks[i].ch,
+             suffix);
     Ui_AddNetwork(line, i);
     if (networks[i].handshake_captured) {
       Ui_SetNetworkColor(i, lv_palette_main(LV_PALETTE_RED));
-    } else {
+    } else if (isCaptureable(i)) {
       Ui_SetNetworkColor(i, lv_palette_main(LV_PALETTE_GREEN));
+    } else {
+      Ui_SetNetworkColor(i, lv_palette_main(LV_PALETTE_GREY));
     }
   }