Update /hivechat/chat/send to include product brief

[humansinstitute]

In future phases we will use the contextTags?: ContextTag[]; passed from the front end to retrieve and build context to be included in our chat request.

In this first phase we will include just the product brief which can be access via: https://github.com/stakwork/sphinx-tribes/blob/master/db/features.go#L331C1-L344C2

This change will add a function to the handler to take in the context tags from the front end (rigth now these will be empty)

Then it will run the getProductBrief function and output this product brief as the variable context

This will then be Included in the stakwork post: "contextTags": context

[humansinstitute]

Assigned - @MahtabBukhari can you approach this detail will be available in 10.