[Investigation] Can we use User Session ID header to store project context?

POCs:

• Web IDE client: Draft: Settings Sync user session ID header POC (!378 - closed)
• Settings Sync BE: Draft: Incorporate Session ID in VSCode Setting... (gitlab!167949 - closed)

Description

We need to prevent different Web IDE Extensions Marketplace contexts from overwriting the Settings Sync BE store. Project and/or group context is required to to retrieve the Extensions Marketplace settings. Although this information is accessible from the Web IDE, we're limited to VSCode's Settings Sync API contract.

We’ll need to find a way to pass this information to the request that is made by VSCode fork. One way to do so is to leverage the user session ID header.

Acceptance Criteria

• POC of using user session ID to store project context.
• Some questions:
  • Can we read/write to sync.user-session-id before the Web IDE boots up VSCode?
  • Are we able to update the BE to respect this User-Session-ID? Will this cause issues with workspaces?
  • Is there another way we can send arbitrary header (like X-Settings-Context-Id) to settings sync requests?