HASPmota add 'tag' attribute for free-form JSON

[s-hadinger]

Description:

HASPmota add free-form tag attribute.

Ex:

{"id":101,"obj":"btn","w%":25,"h%":100,"text":"\uF053","tag":{"wibble":1,"something":"a thing"}}

The tag attribute is added when events are published:

HSP: publish {"hasp":{"p0b101":{"event":"down","tag":{"wibble":1,"something":"a thing"}}}}

Checklist:

• The pull request is done against the latest development branch
• Only relevant files were touched
• Only one feature/fix was added per PR and the code change compiles without warnings
• The code change is tested and works with Tasmota core ESP8266 V.2.7.8
• The code change is tested and works with Tasmota core ESP32 V.3.1.0.241206
• I accept the CLA.

NOTE: The code change must pass CI tests. Your PR cannot be merged unless tests pass