fix for last used font tracking

Last used font is tracked by all font setters.

v1.0.3

• drawString rewritten on top of lcd.drawString + top_left text datum, returning textWidth so callers can detect overflow precisely (thanks @oe1wkl).
• New getLGFX() accessor exposes the underlying lgfx::LGFX_Device* so applications can drop down to LovyanGFX directly (e.g. for full-screen sprite work). Guarded to the ST7789 / ILI9341 builds.

allow SPI sharing

v1.0.1

increase lib version

first release

Initial release