Set namespace type when bootstrapping VSA

What does this MR do and why?

This MR addresses 2 issues:

• Fixes the feature flag actor for the vsa_group_and_project_parity feature flag, ensuring we see the correct UI when the feature flag is enabled, related to !114056 (merged)
• Passes the namespace type to the frontend to determine if we are using a project or group namespace

This is partially a follow-up to !115821 (merged)

Screenshots or screen recordings

The feature flag was incorrectly scoped to groups instead of projects, with the feature flag enabled for a group but disabled for a project we would be indefinitely stuck in the Data is aggregating screen. The correct behaviour is to show the FOSS project level VSA UI.

Before - FF disabled	After - FF disabled

How to set up and validate locally

1. Create a new project

2. Visit VSA for any project - you will see the FOSS view

3. Enable the vsa_group_and_project_parity feature flag

   Feature.enable(:vsa_group_and_project_parity)

4. Ensure you're on an GitLab Premium+ plan

5. Visit VSA for any project - you will see the "Create custom value stream" empty state

6. Create a custom value stream for the project - note the instructions are for groups, but its the same process

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #382496 (closed)