Import ESP_UniClock (upstream 1189810)

Vendored from https://github.com/gpeter62/ESP_UniClock: the sketch
source, the web UI and the libraries the ESP8266 build needs, unpacked
from the bundled zips. Adds a PlatformIO project for the ESP-12. The
source is unchanged; local changes follow as separate commits.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

firmware/uniclock/lib/ArduinoJson/extras/ci/espidf/main/CMakeLists.txt

@@ -0,0 +1,6 @@
+# ArduinoJson - https://arduinojson.org
+# Copyright © 2014-2022, Benoit BLANCHON
+# MIT License
+
+idf_component_register(SRCS "main.cpp"
+                       INCLUDE_DIRS "")

firmware/uniclock/lib/ArduinoJson/extras/ci/espidf/main/component.mk

@@ -0,0 +1,4 @@
+#
+# "main" pseudo-component makefile.
+#
+# (Uses default behaviour of compiling all source files in directory, adding 'include' to include path.)

firmware/uniclock/lib/ArduinoJson/extras/ci/espidf/main/main.cpp

@@ -0,0 +1,16 @@
+// ArduinoJson - https://arduinojson.org
+// Copyright © 2014-2022, Benoit BLANCHON
+// MIT License
+
+#include <ArduinoJson.h>
+
+extern "C" void app_main() {
+  char buffer[256];
+  StaticJsonDocument<200> doc;
+
+  doc["hello"] = "world";
+  serializeJson(doc, buffer);
+  deserializeJson(doc, buffer);
+  serializeMsgPack(doc, buffer);
+  deserializeMsgPack(doc, buffer);
+}