Integrate AIP31068 LCD support into CharacterLcd

[asp2286]

Summary

• Iot.Device.CharacterLcd.Lcd1602 cannot drive AIP31068-based displays because the controller requires an extended initialization sequence and contrast configuration.
• The new Aip31068Lcd binding lives outside the common CharacterLcd abstraction, so samples and helpers that expect Lcd1602 remain incompatible.

Expected behavior

Developers should be able to instantiate Lcd1602 with an I²C transport targeting an AIP31068 controller and see the display initialize with the proper contrast/booster settings without patching the driver.

Actual behavior

Lcd1602 issues the standard HD44780 initialization sequence, which leaves AIP31068 displays blank or stuck with incorrect contrast. The higher-level CharacterLcd helpers therefore fail to work when the screen uses this controller.

Reproduction steps

1. Connect an AIP31068-based 16x2 LCD (e.g., labeled "AIP31068" or "WS0010") over I²C at address 0x3E.
2. Instantiate Lcd1602 with an I2cDevice configured for that bus/address.
3. Run any of the CharacterLcd samples that target Lcd1602.
4. Observe that the display never leaves the blank/low-contrast state because the extended initialization is missing.

Proposed fix

• Extend Lcd1602 so it can optionally execute the AIP31068 initialization flow (function set with IS=1, contrast parameters, booster enable, etc.).
• Expose knobs for contrast and booster so the screen can be tuned at runtime.
• Update CharacterLcd samples/documentation to mention the capability and demonstrate its usage.

Additional context

• Reference: Controller datasheet describing the extended command set (AIP31068 / WS0010).
• Related work: src/devices/CharacterLcd/Aip31068Lcd.cs implements the required sequence but is disconnected from Lcd1602.