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/SUPPORT.md

@@ -0,0 +1,27 @@
+# ArduinoJson Support
+
+First off, thank you very much for using ArduinoJson.
+
+We'll be very happy to help you, but first please read the following.
+
+## Before asking for help
+
+1. Read the [FAQ](https://arduinojson.org/faq/?utm_source=github&utm_medium=support)
+2. Search in the [API Reference](https://arduinojson.org/api/?utm_source=github&utm_medium=support)
+
+If you did not find the answer, please create a [new issue on GitHub](https://github.com/bblanchon/ArduinoJson/issues/new).
+
+It is OK to add a comment to a currently opened issue, but please avoid adding comments to a closed issue.
+
+## Before hitting the Submit button
+
+Please provide all the relevant information:
+
+* Good title
+* Short description of the problem
+* Target platform
+* Compiler model and version
+* [MVCE](https://stackoverflow.com/help/mcve)
+* Compiler output
+
+Good questions get fast answers!