tests: Add board qualification test for I2C bus scan.

[nedseb]

Description

Add a board qualification test that scans the internal I2C bus and verifies all expected sensor addresses are present.

Scenario: tests/scenarios/board_i2c_scan.yaml

Tests

1. I2C bus scan finds expected devices — scan I2C bus 1 and verify all expected addresses are found:

   • 0x20 = MCP23009E (I/O expander)
   • 0x29 = VL53L1X (distance)
   • 0x39 = APDS9960 (light/gesture/proximity)
   • 0x55 = BQ27441 (battery gauge)
   • 0x5C = WSEN-HIDS (humidity/temperature)
   • 0x5D = WSEN-PADS (pressure)
   • 0x5F = HTS221 (humidity/temperature)

2. No unexpected I2C devices — verify no unknown addresses appear on the bus (also includes 0x1E = LIS2MDL magnetometer as known).

Depends on

• tests: Extend test framework for driverless board qualification scenarios. #83 (framework extension for type: board scenarios)

Run command

pytest tests/ --port /dev/ttyACM0 -s -k "board_i2c_scan"