refactor(docs): Refactor the development section (#2438)

docs/docs/development/local-toolchain/posix-board.md

@@ -0,0 +1,38 @@
+---
+title: Native Posix board target
+---
+
+In order to iterate quickly on firmware features, it can
+be helpful to build and run the firmware on your local
+workstation, with generated virtual press/release events
+flowing into the handler functions.
+
+## Prerequisites
+
+In order to build targeting the `native_posix` board, you need to setup your system
+with a compiler that can target 32-bit POSIX.
+
+On Debian, you can do this with:
+
+```sh
+apt install -y gcc-multilib
+```
+
+## Building
+
+To do this, you can build ZMK targeting the
+`native_posix_64` board.
+
+```sh
+west build --pristine --board native_posix_64 -- -DZMK_CONFIG=tests/none/normal/
+```
+
+Once built, you can run the firmware locally:
+
+```
+./build/zephyr/zmk.exe
+```
+
+## Virtual Key Events
+
+The virtual key presses are hardcoded in `boards/native_posix_64.overlay` file, should you want to change the sequence to test various actions like Mod-Tap, etc.