Agentic autofix generation for code scanning alerts [GA]

### Value Prop
With agentic autofix for code scanning alerts, users can automatically resolve security issues in their code by assigning alerts to an advanced agent that generates and submits pull requests with fixes. This streamlines the remediation process, saving time and reducing manual effort for development and security teams.

### Expected Outcome
By making agentic autofix generally available to all paying GitHub Advanced Security and code security users, more organizations can quickly address vulnerabilities and maintain secure codebases. The goal is to increase the speed and efficiency of fixing code scanning alerts, leading to stronger security and less operational overhead.