* make pins optional for Spi::new (master, full-duplex mode)
* add additional method to setup spi pins (master, full-duplex mode)
* add additional method to setup spi pins (master, half-duplex mode)
* remove generic type parameters for Spi::new
* update documentation
* make `with_pins` could be chained
* update CHANGELOG.md
* update CHANGELOG.md
* make the return value of a method like `with_{*}` owned
* fix (maybe?) all broken examples caused by the change (esp32-hal)
* fix (maybe?) all broken examples caused by the change (esp32c2-hal)
* fix (maybe?) all broken examples caused by the change (esp32c3-hal)
* fix (maybe?) all broken examples caused by the change (esp32c6-hal)
* fix (maybe?) all broken examples caused by the change (esp32h2-hal)
* fix (maybe?) all broken examples caused by the change (esp32s2-hal)
* fix (maybe?) all broken examples caused by the change (esp32s3-hal)
* rerun 'cargo fmt' for esp-hal-common
* rerun 'cargo fmt' for the rest of examples
* Move SPI-related traits into their own preludes in the `spi` module
* Remove the `embedded-hal-async` trait re-exports and the `eh1` module from the prelude
* Update `CHANGELOG.md`
* Refactor the `spi` and `spi_slave` modules into a single `spi` module
* Update import paths in examples as needed
* Extract some common types from `spi::master` into the root `spi` module
* Fix imports in examples (again)
* Documentation fixes/improvements
* Remove unnecessary re-exports
* Update `CHANGELOG.md`
