This update for micropython fixes the following issues:

Changes in micropython:

- Build with mbedtls-3.6.5 instead of bundled 3.6.2 to fix CVE-2025-59438

Version 1.26.0:

  * Added machine.I2CTarget for creating I2C target devices on multiple ports.
  * New MCU support: STM32N6xx (800 MHz, ML accel) & ESP32-C2 (WiFi + BLE).
  * Major float accuracy boost (~28% → ~98%), constant folding in compiler.
  * Optimized native/Viper emitters; reduced heap use for slices.
  * Time functions standardized (1970–2099); new boards across ESP32, SAMD, STM32, Zephyr.
  * ESP32: ESP-IDF 5.4.2, flash auto-detect, PCNT class, LAN8670 PHY.
  * RP2: compressed errors, better lightsleep, hard IRQ timers.
  * Zephyr v4.0.0: PWM, SoftI2C/SPI, BLE runtime services, boot.py/main.py support.
  * mpremote adds fs tree, improved df, portable config paths.
  * Updated lwIP, LittleFS, libhydrogen, stm32lib; expanded hardware/CI tests.