[Keyboard] Add keyboard "Spreadwriter" (#17031)

Co-authored-by: Joel Challis <git@zvecr.com>
Co-authored-by: Drashna Jaelre <drashna@live.com>

keyboards/takashicompany/spreadwriter/keymaps/via/config.h

@@ -0,0 +1,20 @@
+// Copyright 2022 takashicompany (@takashicompany)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#define DYNAMIC_KEYMAP_LAYER_COUNT 7
+
+//------------------------------------------------------------------------------
+// Rotary Encoder
+//------------------------------------------------------------------------------
+// Encoder triggers specific key matrix position,
+// when turn knob clockwise or counterclockwise.
+// This is handy to assign key codes by VIA.
+
+// Number of endoder
+#define ENCODERS 1
+
+// Mappings of encoder rotation to key position in key matrix.
+#define ENCODERS_CW_KEY  { { 0, 4 }}
+#define ENCODERS_CCW_KEY { { 6, 0 }}