🚀 Feature: typed context for better IDE support

[trashcoder]

🔖 Feature description

a typed context would improve the development.

🎤 Pitch

E.g. actually i don't know if my sdk-dart supports context.req.bodyText or context.req.body.

👀 Have you spent some time to check if this issue has been raised before?

• [X] I checked and didn't find similar issue

🏢 Have you read the Code of Conduct?

• [X] I have read the Code of Conduct