Revise AI rules and extend editor support to Claude, Copilot, and Antigravity

[tjementum]

Summary & Motivation

Restructure and consolidate AI rules to establish .claude as the source of truth, with automatic synchronization to Cursor, Windsurf, GitHub Copilot, and Google Antigravity editors. This change improves maintainability by having a single canonical location for all AI rules while ensuring compatibility across different AI-assisted development tools.

• Review all AI rules and ensure they follow the latest practice
• Reorganize all rules into the .claude/rules/** and .claude/commands/**
• Consolidate main AI rules into AGENTS.md for Windsurf, Cursor, Antigravity compatibility
  Use a symbolic link to have CLAUDE.md and .github/copilot-instructions.md contain the same content as AGENTS.md
• Add workflow files for implementing tasks, reviewing code, creating PRDs, and end-to-end test processes
• Create mapping support for product management tools (Linear, Azure DevOps, Jira)
• Implement sync-ai-rules CLI command that synchronizes rules from .claude to .cursor, .windsurf, .agents, and .github/copilot
• Refactor commit workflow with streamlined process and relocate to commands root

Downstream projects

1. Update AGENTS.md

• Change [CLI_ALIAS]="pp" to your Developer CLI alias
• Change PRODUCT_MANAGEMENT_TOOL="Linear" to your product management tool. Possible values are AzureDevOps, Jira, and Linear. This requires you to have an MCP server for this tool. Use Markdown to use local file system.

2. If custom rules or adjustments were made migrate them to .claude/rules and .claude/workflows. And then run the [CLI_ALIAS] sync-ai-rules

Checklist

• I have added tests, or done manual regression tests
• I have updated the documentation, if necessary

[linear]

PP-644 Update AI rules and workflows to support Claude Code, Antigravity, and GitHub Copilot