feat(go): Added simulated document-based context support

[sahdev77]

Addition of augmentWithContext middleware to simulated document-based grounding support.
Resolving : #1926

Checklist (if applicable):

• PR title is following https://www.conventionalcommits.org/en/v1.0.0/
• Tested (manually, unit tested, etc.)
• Docs updated (updated docs or a docs bug required)

[apascal07]

Like the other middleware, please either write or adjust an existing sample (there are samples that pass docs into the request already) to verify that it does what we want.

[apascal07]

I think some of the generator_test.go tests are failing because they pass in docs but previous those docs did nothing. Please update.