Repository security advisories

[jurre]

This pull request adds new functionality to list security advisories for both individual repositories and entire organizations, along with corresponding tests and documentation updates. This builds on #919 and the PR is stacked against that, we can either merge it into that branch, or have it rebased against main when it lands.

[Copilot]

Pull Request Overview

This pull request adds new functionality to list security advisories for both individual repositories and entire organizations, expanding the existing security advisory tools beyond global advisories.

• Implements two new tools: list_repository_security_advisories and list_org_repository_security_advisories
• Adds comprehensive test coverage for both new functions with various scenarios including success cases and error handling
• Updates documentation to include the new tools in the README

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
pkg/github/tools.go	Registers the two new security advisory tools in the default toolset
pkg/github/security_advisories.go	Implements the core logic for listing repository and organization security advisories
pkg/github/security_advisories_test.go	Adds comprehensive test suites for both new functions
README.md	Documents the new tools with their parameters and descriptions

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[tommaso-moro]

Lgtm! Great one 🚀

The base branch was changed.