Resolve This Vulnerability - Service classes to retrieve a code fix suggestion for a respective vulnerability

Resolve Vulnerability's behaviour is primarily backend driven using a variety of established GitLab behaviour to provide new functionality. We will need to write a few new services to facilitate this functionality.

In short, ResolveVulnerability will need to:

• Receive and handle a mutation request from a user to provide a vulnerability resolution for a specific vulnerability.
• Process the request asynchronously
• Generate a prompt request a patch or diff from the AI provider
• Receive the response, and parse it for quality
• Attempt to form a valid diff with the provided code
• Create a branch, and apply the diff to the branch
• Create an MR for the branch
• Link the new MR to the original Vulnerability
• Respond to the User with the link to the new MR

Flow Diagram

Implementation Plan

• Implement The ResolveVulnerability AiAction using the existing Ai mutation pattern used by ExplainThisVulnerability
• Implement ResolveVulnerabilityCompletion and Template services to generate a Resolve prompt for the vulnerability and request the result from the AI provider
• Implement a ResolveVulnerabilityService which uses the Ai response, attempts to form an appropriate diff with it, and then applies it to a new Branch and MR which can be sent back to the user.