[Keymap] Added HHKB Keymap and user config (#8119)

* Added my config

* Update my keymap

* Improve quality of brett.c

* Finish cleaning brett.c

* Remove QMK_FIRMWARE_H

* Update keyboards/hhkb/keymaps/brett/keymap.c

Co-Authored-By: Ryan <fauxpark@gmail.com>

Co-authored-by: Ryan <fauxpark@gmail.com>

users/brett/brett.c

@@ -0,0 +1,61 @@
+#include "brett.h"
+
+char * get_key(uint16_t keycode) {
+    switch (keycode) {
+        case FAT_ARROW:
+            return "=>";
+        case SKINNY_ARROW:
+            return "->";
+        case REVERSE_ARROW:
+            return "<-";
+        case CONCAT:
+            return "<>";
+        case MAP:
+            return "<$>";
+        case MAP_FLIPPED:
+            return "<#>";
+        case FLAP:
+            return "<@>";
+        case PIPE:
+            return "|>";
+        case ALT:
+            return "<|>";
+        case APPLY:
+            return "<*>";
+        case AND:
+            return "&&";
+        case OR:
+            return "||";
+        case BIND:
+            return ">>=";
+        case BIND_FLIPPED:
+            return "=<<";
+        case DOUBLE_COLON:
+            return "::";
+        case VOID_LEFT:
+            return "<$";
+        case VOID_RIGHT:
+            return "$>";
+        default:
+            return "";
+    }
+}
+
+bool process_record_user(uint16_t keycode, keyrecord_t *record) {
+    bool pressed = record->event.pressed;
+    switch (keycode) {
+        case FAT_ARROW ... DOUBLE_COLON:
+            if (pressed) {
+                send_string(get_key(keycode));
+            }
+            return false;
+        case FLASH:
+            if (!pressed) {
+                SEND_STRING("make -j8 --output-sync " QMK_KEYBOARD ":" QMK_KEYMAP ":flash" SS_TAP(X_ENTER));
+                reset_keyboard();
+            }
+            return false;
+        default:
+            return true;
+    }
+}