firmware: v3 — nuevo diseño web HUD

- Interfaz completamente rediseñada: tema militar/racing oscuro
- Fondo con grid animado, tipografia Orbitron
- Barras de potencia estilo LED (6 segmentos verde→rojo)
- Botones angulares con glow rojo (traccion) y azul (camara)
- Flechas CSS puras, crosshair en centro de camara
- Esquinas HUD animadas sobre el stream
- camera_index.h regenerado desde data/index.html (4.6KB gzipped)
- gen_header.py para regenerar el header en el futuro

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

gen_header.py

@@ -0,0 +1,19 @@
+import gzip, os, sys
+os.chdir("d:/Proyectos/Arduino/Arduino-Car/Esp32Cam/data")
+with open("index.html","rb") as f:
+    data = f.read()
+with gzip.open("index.html.gz","wb",compresslevel=9) as f:
+    f.write(data)
+compressed = open("index.html.gz","rb").read()
+print(f"Original: {len(data)} bytes  Gzipped: {len(compressed)} bytes")
+lines  = ["// Auto-generado desde data/index.html"]
+lines += [f"#define index_html_gz_len {len(compressed)}"]
+lines += ["static const uint8_t index_html_gz[] = {"]
+for i in range(0, len(compressed), 16):
+    chunk = compressed[i:i+16]
+    lines.append("  " + ", ".join(f"0x{b:02X}" for b in chunk) + ",")
+lines[-1] = lines[-1].rstrip(",")
+lines += ["};"]
+with open("../camera_index.h","w") as f:
+    f.write("\n".join(lines) + "\n")
+print("camera_index.h generado OK")