handshake-capture-c6 v1.0.4: persist captured BSSIDs, PCAP EAPOL recount

- /cap_bssids.txt append on save; handshakeLoadPersistedBssids after SD mount
- Boot order: SD then load file then first WiFi scan (reds match SD)
- Pre-save walk of in-memory PCAP counting EAPOL-Key frames
- SD_AppendLine / SD_ForEachLine; drop g_sd_ready clear on write fail
- README + MUST_DO updates

Made-with: Cursor

handshake-capture-c6/HandshakeCapture.h

@@ -6,7 +6,7 @@
 #include <SD.h>
 
 /** Semantic version (Serial banner + support). */
-#define HANDSHAKE_FIRMWARE_VERSION "1.0.3"
+#define HANDSHAKE_FIRMWARE_VERSION "1.0.4"
 
 #ifndef HANDSHAKE_DEBUG
 #define HANDSHAKE_DEBUG 0
@@ -38,6 +38,9 @@
 /** Heuristic threshold only; frames are not validated as distinct 4-way steps. */
 #define HANDSHAKE_EAPOL_FRAMES 4
 
+/** SD file: one line per BSSID `AA:BB:CC:DD:EE:FF` — loaded on boot so restarts skip re-capture. */
+#define HANDSHAKE_CAPTURED_BSSID_FILE  "/cap_bssids.txt"
+
 // Two APs at once: less on-air contention, more time per target before rotating.
 #define MAX_SLOTS 2
 #define MAX_NETWORKS 20
@@ -103,6 +106,8 @@ extern int current_channel;
 extern CapturePhase capturePhase;
 
 void handshakeCaptureInit();
+/** Call after SD_Init() succeeds — merges file into RAM BSSID cache (survives reboot). */
+void handshakeLoadPersistedBssids();
 void handshakeCaptureProcessPending();
 void refillSlots();
 bool wasBssidCaptured(const uint8_t* bssid);