Macros in JSON keymaps (#14374)

* macros in json keymaps

* add advanced macro support to json

* add a note about escaping macro strings

* add simple examples

* format json

* add support for language specific keymap extras

* switch to dictionaries instead of inline text for macros

* use SS_TAP on the innermost tap keycode

* add the new macro format to the schema

* document the macro limit

* add the json keyword for syntax highlighting

* fix format that vscode screwed up

* Update feature_macros.md

* add tests for macros

* change ding to beep

* add json support for SENDSTRING_BELL

* update doc based on feedback from sigprof

* document host_layout

* remove unused var

* improve carriage return handling

* support tab characters as well

* Update docs/feature_macros.md

Co-authored-by: Nick Brassel <nick@tzarc.org>

* escape backslash characters

* format

* flake8

* Update quantum/quantum_keycodes.h

Co-authored-by: Nick Brassel <nick@tzarc.org>

keyboards/handwired/pytest/macro/info.json

@@ -0,0 +1,10 @@
+{
+  "maintainer": "qmk",
+  "layouts": {
+    "LAYOUT_custom": {
+      "layout": [
+        { "label": "KC_Q", "matrix": [0, 0], "w": 1, "x": 0, "y": 0 }
+      ]
+    }
+  }
+}