tests: Add board qualification test for I2C bus scan.

[nedseb]

Summary

Closes #84
Depends on #89 (framework extension)

Adds a board qualification test scenario that scans the internal I2C bus, verifies all expected device addresses are present, and checks the WHO_AM_I / device ID register of each component.

Scenario: tests/scenarios/board_i2c_scan.yaml

Bus scan tests (2 tests)

Test	Description
I2C bus scan finds expected devices	Scans I2C(1) and verifies 9 expected addresses
No unexpected I2C devices	Verifies no unknown addresses on the bus

WHO_AM_I / Device ID tests (7 tests)

Test	Address	Register	Expected
LIS2MDL WHO_AM_I	0x1E	0x4F	0x40
MCP23009E IODIR default	0x20	0x00	0xFF
VL53L1X model ID	0x29	0x010F	0xEACC
APDS9960 device ID	0x39	0x92	0xAB
WSEN-PADS device ID	0x5D	0x0F	0xB3
HTS221/WSEN-HIDS device ID	0x5F	0x0F	0xBC
ISM330DL WHO_AM_I	0x6B	0x0F	0x6A

Expected I2C addresses (7-bit):

• 0x1E LIS2MDL, 0x20 MCP23009E, 0x29 VL53L1X, 0x39 APDS9960
• 0x3B STM32F103CB, 0x55 BQ27441, 0x5D WSEN-PADS
• 0x5F HTS221/WSEN-HIDS, 0x6B ISM330DL

Note: MCP23009E requires releasing RST_EXPANDER pin before scan.

How to test

# Mock tests (no regression)
pytest tests/ -k mock

# Collect board tests (no hardware needed)
pytest tests/ -k board_i2c_scan --collect-only

# Run on hardware (requires STeaMi board)
pytest tests/ --port /dev/ttyACM0 -k board_i2c_scan -s -v

Test plan

• ruff check tests/ — passed
• pytest tests/ -k mock — 41 passed (no regression)
• Board tests correctly collected and skipped without --port
• Hardware validation on STeaMi board — 9 passed

[Copilot]

Pull request overview

Adds a new board-level qualification YAML scenario to validate the STeaMi board’s internal I2C bus population by scanning I2C(1) on hardware and asserting that expected devices are present and no unknown devices appear (per #84, leveraging the “board scenario” framework from #89).

Changes:

• Introduces board_i2c_scan board scenario with two hardware-only tests: (1) required-address presence and (2) no-unexpected-addresses check.
• Encodes the expected/known I2C address sets directly in the scenario scripts.

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[nedseb]

Corrections suite à la review Copilot (58277d9) :

• Meilleur diagnostic : result retourne maintenant la liste des adresses manquantes/inattendues (triée) avec expect: [], au lieu d'un booléen. En cas d'échec, le message d'erreur affichera les adresses problématiques.

[Copilot]

Pull request overview

Adds a new board-level qualification YAML scenario to validate the STeaMi board’s internal I2C bus by scanning for expected devices and performing a few identification-register sanity checks, leveraging the existing type: board scenario runner behavior.

Changes:

• Introduces a new type: board scenario that scans I2C(1) and asserts a fixed set of expected/known addresses.
• Adds per-device WHO_AM_I / ID-register reads for several components to confirm devices respond correctly beyond just presence on the bus.

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[nedseb]

Réponses aux commentaires Copilot :

expect_true → expect: [] (commentaires 1 et 2) — Déjà corrigé dans un commit précédent : les tests retournent la liste des adresses manquantes/inattendues avec expect: [].

Adresses incohérentes avec la description PR (commentaire 3) — Corrigé : la description PR est mise à jour avec les bonnes adresses (0x3B=STM32F103CB, 0x6B=ISM330DL ajoutés, 0x5C retiré).

Tests WHO_AM_I non mentionnés (commentaire 4) — Corrigé : la description PR liste maintenant les 9 tests (2 scan + 7 WHO_AM_I/Device ID) avec un tableau détaillé des registres et valeurs attendues.