[Keyboard] Add pocketpad (#20229)

Co-authored-by: jack <0x6a73@protonmail.com>

keyboards/butterkeebs/pocketpad/readme.md

@@ -0,0 +1,27 @@
+# PocketPad
+
+![PocketPad](https://tinyurl.com/2hffvnvb)
+
+*The PocketPad is a tiny 18 key macropad/numpad using 6mm tactile switches.*
+
+* Keyboard Maintainer: [ButterKeebs](https://github.com/butterkeebs)
+* Hardware Supported: *Supports current V1.0.0 PocketPad PCB and Elite C / pin compatible MCU boards.*
+* Hardware Availability: *Currently not for sale*
+
+Make example for this keyboard (after setting up your build environment):
+
+    make butterkeebs/pocketpad:default
+
+Flashing example for this keyboard:
+
+    make butterkeebs/pocketpad:default:flash
+
+See the [build environment setup](https://docs.qmk.fm/#/getting_started_build_tools) and the [make instructions](https://docs.qmk.fm/#/getting_started_make_guide) for more information. Brand new to QMK? Start with our [Complete Newbs Guide](https://docs.qmk.fm/#/newbs).
+
+## Bootloader
+
+Enter the bootloader in 3 ways:
+
+* **Bootmagic reset**: Hold down the key at (0,0) in the matrix (usually the top left key or Escape) and plug in the keyboard
+* **Physical reset button**: Briefly press the button on the back of the PCB. (Not available on Revision 1.0.0 PCB)
+* **Keycode in layout**: Press the key mapped to `QK_BOOT` if it is available