fix: FTP passive mode, battery UI position, SD path traversal

- Add ftpSrv.setLocalIp() for correct PASV response IP (fixes transfers)
- Move battery indicator to WiFi SSID line, right-aligned
- Fix battery label tilt: fixed width + LV_TEXT_ALIGN_RIGHT
- Fix calcDirSize: use f.path() for full path in recursive walk

src/main.cpp

@@ -108,9 +108,10 @@ static uint64_t calcDirSize(fs::FS &fs, const char *dirname) {
     File f;
     while ((f = root.openNextFile())) {
         if (f.isDirectory()) {
-            String path = f.name();
+            /* On ESP32 Arduino 3.x, f.path() returns the full path */
+            String fullPath = String(f.path());
             f.close();
-            total += calcDirSize(fs, path.c_str());
+            total += calcDirSize(fs, fullPath.c_str());
         } else {
             total += f.size();
             f.close();
@@ -442,8 +443,11 @@ static void initFtp() {
     Serial.println("[FTP] Starting FTP server (user: kode, port: 21)...");
     ftpSrv.setCallback(ftpCallback);
     ftpSrv.setTransferCallback(ftpTransferCallback);
+    /* Set local IP so PASV mode sends the correct address to clients */
+    ftpSrv.setLocalIp(WiFi.localIP());
     ftpSrv.begin("kode", "kode");
-    Serial.println("[FTP] FTP server ready");
+    Serial.printf("[FTP] FTP server ready (PASV IP: %s, data port: 50009)\n",
+                  WiFi.localIP().toString().c_str());
     ui_set_ftp("Idle");
 }