[instructions] Sync github-agentic-workflows.md with v0.35.1

[github-actions]

Instructions Update - Synchronized with v0.35.1

This PR updates the github-agentic-workflows.md file based on changes in v0.35.0/v0.35.1 releases.

Changes Made

• Added allowed-github-references field documentation to safe-outputs global configuration
• Added allowed-domains field documentation to safe-outputs global configuration (previously undocumented)

Documentation Commits Reviewed

• 0963b76 - Remove Campaign Improvements & Future Directions documentation page (no impact on instructions file)

Feature Details

allowed-github-references (new in v0.35.0):

• Controls which GitHub repository references (#123, owner/repo#456) are allowed in workflow output
• References to unlisted repositories are escaped with backticks to prevent timeline items
• Particularly useful for SideRepoOps workflows to prevent automation timeline clutter
• Configuration options: [] (escape all), ["repo"] (current repo only), ["repo", "owner/other"] (specific repos), or unspecified (all allowed)

allowed-domains:

• Controls which domains are allowed in URLs within safe output content
• URLs from unlisted domains are replaced with (redacted)
• GitHub domains are always included by default

Validation

• Followed prompting best practices (imperative mood, minimal examples)
• Maintained technical tone and brevity
• Updated only necessary sections (global safe-output configuration)
• Verified accuracy against current codebase (checked schema, tests, and documentation)
• Removed no content (pure addition of missing documentation)
• Added concise, representative example for allowed-github-references

AI generated by Instructions Janitor