Replace custom issue assistant with GitHub Agentic Workflow

[DimaBir]

Replace Issue Assistant with GitHub Agentic Workflows

Changes

• Removed custom issue assistant implementation (500+ lines YAML/JS)
• Removed .github/issue-assistant/ folder and security.js
• Removed .github/workflows/issue-assistant.yml
• Added msdo-issue-assistant.md - new agentic workflow (natural language)
• Added msdo-issue-assistant.lock.yml - compiled workflow with guardrails

Benefits

• Simpler: ~100 lines markdown vs 500+ lines YAML/JS
• Built-in security: sandboxed execution, output sanitization, threat detection
• No custom secrets needed for prompts (uses COPILOT_GITHUB_TOKEN)
• Easier to maintain: edit plain English instructions
• Uses GitHub's official [Agentic Workflows](https://github.github.com/gh-aw/) framework

How it works

• Triggers on new issues and comments
• AI analyzes issue content against MSDO wiki knowledge
• Responds with helpful info or requests more details
• Applies labels: bug, feature, question, needs-info, needs-maintainer

[Copilot]

Pull request overview

This PR replaces a custom 500+ line issue assistant implementation with GitHub's official Agentic Workflows framework. The change removes custom YAML/JavaScript code in favor of a natural language workflow definition that compiles to a managed execution environment with built-in security features.

Changes:

• Removed custom .github/workflows/issue-assistant.yml (577 lines) and .github/issue-assistant/src/security.js (249 lines)
• Added .github/workflows/msdo-issue-assistant.md (113 lines) - natural language workflow definition
• Added .github/workflows/msdo-issue-assistant.lock.yml (1062 lines) - auto-generated compiled workflow with sandboxing, threat detection, and safe outputs
• Added .github/aw/actions-lock.json for action version pinning and .gitattributes for lock file merge strategy

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
.github/workflows/issue-assistant.yml	Removed custom issue assistant workflow with state management, security validation, and AI response generation
.github/issue-assistant/src/security.js	Removed custom security module with prompt injection detection, rate limiting, and input sanitization
.github/workflows/msdo-issue-assistant.md	Added natural language workflow defining issue triage bot behavior, rules, and response patterns
.github/workflows/msdo-issue-assistant.lock.yml	Added compiled workflow with sandboxed execution, threat detection, and managed safe outputs
.github/aw/actions-lock.json	Added action version locks for reproducible builds
.gitattributes	Added merge strategy for auto-generated lock files

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[amgadalaa]

Review