feat(compass-assistant): add global per-conversation instructions COMPASS-9766

[lerouxb]

COMPASS-9766

[Copilot]

Pull Request Overview

This PR adds global per-conversation instructions to the Compass assistant, allowing the chatbot to distinguish between different application contexts (Atlas Data Explorer vs MongoDB Compass) when providing responses.

• Adds a method to determine the appropriate app name for prompts based on API URL preset
• Introduces conversation instructions that inform the assistant which application it's running in
• Updates the docs provider transport to accept and use instructions parameter

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/compass-generative-ai/src/atlas-ai-service.ts	Adds getAppNameForPrompt() method to return context-appropriate app names
packages/compass-generative-ai/src/atlas-ai-service.spec.ts	Adds test coverage for the new app name method
packages/compass-assistant/src/prompts.ts	Creates buildConversationInstructionsPrompt() function to generate instructions
packages/compass-assistant/src/docs-provider-transport.ts	Updates constructor to accept instructions and passes them to OpenAI provider
packages/compass-assistant/src/compass-assistant-provider.tsx	Integrates the new instruction system into the chat transport

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[gagik]

code looks good, I think we should have a better prompt at this stage since I find it to work much better if we provide a specific instruction

[lerouxb]

I realised I have to use the instructions in the braintrust evals too, so I just incorporated #7256 because I already did the work there.