Add STM32WBA55CG Nucleo port (wolfHAL backend)

Adds a wolfBoot port for the STM32WBA55CG Nucleo (Cortex-M33) on the wolfHAL backend, and bumps lib/wolfHAL to the latest.

Changes

• New stm32wba target in arch.mk (Cortex-M33 / ARMv8-M)
• New board hal/boards/stm32wba55cg_nucleo/ (board.c/.h/.mk) using the upstream wolfHAL flash/gpio/uart drivers
• Linker script hal/stm32wba.ld (1 MB flash @ 0x08000000, 128 KB RAM)
• Example config config/examples/stm32wba.config (ECC256/SHA256)
• Bump lib/wolfHAL
• Add the new config to CI (test-configs.yml)

Test plan

• Builds clean for config/examples/stm32wba.config
• Flash factory.bin @ 0x08000000; confirm it verifies + boots a signed app