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/ESPAsyncTCP/ssl/gen_server_cert.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+
+cat > ca_cert.conf << EOF  
+[ req ]
+distinguished_name     = req_distinguished_name
+prompt                 = no
+
+[ req_distinguished_name ]
+ O                      = Espressif Systems
+EOF
+
+openssl genrsa -out axTLS.ca_key.pem 2048
+openssl req -new -config ./ca_cert.conf -key axTLS.ca_key.pem -out axTLS.ca_x509.req
+openssl x509 -req -sha1 -days 5000 -signkey axTLS.ca_key.pem -CAkey axTLS.ca_key.pem -in axTLS.ca_x509.req -out axTLS.ca_x509.pem
+
+cat > certs.conf << EOF  
+[ req ]
+distinguished_name     = req_distinguished_name
+prompt                 = no
+
+[ req_distinguished_name ]
+ O                      = axTLS on ESP8266
+ CN                     = esp8266.local
+EOF
+
+openssl genrsa -out axTLS.key_1024.pem 1024
+openssl req -new -config ./certs.conf -key axTLS.key_1024.pem -out axTLS.x509_1024.req
+openssl x509 -req -sha1 -CAcreateserial -days 5000 -CA axTLS.ca_x509.pem -CAkey axTLS.ca_key.pem -in axTLS.x509_1024.req -out axTLS.x509_1024.pem
+
+openssl rsa -outform DER -in axTLS.key_1024.pem -out axTLS.key_1024
+openssl x509 -outform DER -in axTLS.x509_1024.pem -out axTLS.x509_1024.cer
+
+cat axTLS.key_1024 > server.key
+cat axTLS.x509_1024.cer > server.cer
+
+rm axTLS.* ca_cert.conf certs.conf