Fix SHT4x temperature and humidity sensor detection by reading unique serial nubmer

[dem1tris]

fixes #7522
fixes #6835

Problem

The current SHT4x and SHT3x environment sensors distinguishing algorithm is wrong. It writes 0x89 and accepts only certain values returned.

registerValue = getRegisterValue(ScanI2CTwoWire::RegisterLocation(addr, 0x89), 2);
if (registerValue == 0x11a2 || registerValue == 0x11da || registerValue == 0x11f3 || registerValue == 0xe9c ||
    registerValue == 0xc8d) {
    type = SHT4X;
    logFoundDevice("SHT4X", (uint8_t)addr.address);
}

Actually, 0x89's answer from SHT4x is the unique serial number, according to the datasheet (p. 4.7).

Fix

The fixed code firstly checks for OPT3001, then uses 0x89 and considers any non-zero value as SHT4x. Otherwise, it's SHT3x. Also note that SHT3x will not respond to the 0x89, since its commands have 2-byte length, according to the datasheet.

🤝 Attestations

• I have tested that my proposed changes behave as described.
• I have tested that my proposed changes do not cause any obvious regressions on the following devices:
  • SHT41 sensor
  • Heltec (Lora32) V3
  • Heltec MeshNode T114

[Copilot]

Pull Request Overview

This PR refactors the I2C sensor detection logic for SHT4X, SHT31, and OPT3001 sensors that share the same I2C addresses (0x44 and 0x45). The detection order and logic have been improved for more reliable identification.

• Changed the detection order to check OPT3001 first, then SHT4X, and finally SHT31 as the fallback
• Simplified the SHT4X detection logic to check for any non-zero value at register 0x89 instead of checking for specific IDs
• Added a debug log statement to trace register values during detection

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