Add STM32WBA65RI NUCLEO board to HIL test bench

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Summary

• Add HIL test configuration for the NUCLEO-WBA65RI board
• UART loopback via LPUART1, SPI loopback via SPI2, plus RNG, HASH, RTC, and ADC tests
• RCC uses HSI at 16 MHz with sai1sel set to HSI (WBA65RI has SAI, unlike WBA52, and the default mux zeroes to PLL1_P)
• Tests excluded from CI (ci.sh) until the board is physically on the HIL shelf

Wiring (Arduino header)

• UART loopback: Wire D9 (PB11, LPUART1_TX) to D8 (PA10, LPUART1_RX)
• SPI loopback: Wire D11 (PC3, SPI2_MOSI) to D12 (PA9, SPI2_MISO)

Hardware-validated tests

All wire-free tests pass on hardware: timer, rng, hash, rtc, adc.
UART and SPI loopback tests pass with wiring in place.

Note: The usart test fails at 2 Mbaud because LPUART1 at 16 MHz HSI can't achieve that speed. The driver should return BaudrateTooHigh but doesn't — this is a pre-existing LPUART driver issue (WBA52 uses LPUART1 too), not specific to this PR.

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Here's the pinout

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@Dirbaio let me know if you need anything else from my end.