feat(just): Add repository branch protection justfile entries

[aRustyDev]

Summary

This PR adds justfile entries for protecting GitHub repositories using branch rulesets, and refactors the entire justfile to use just built-in functions and a global target_repo variable.

Changes

New Features

• Branch Protection Recipes: New justfile recipes for managing repository branch protection:

  • protect-repo [repo] - Apply all branch protection rulesets
  • apply-ruleset [repo] <file> - Apply a single ruleset from JSON file
  • unprotect-repo [repo] - Remove all rulesets
  • list-rulesets [repo] - List all rulesets for a repository

• Initialization System:

  • init - Interactive first-time setup that sets target_repo
  • set-target <repo> - Non-interactive way to change target repository
  • Self-modifying justfile to persist the target repository

New Files

• .github/rulesets/main-branch-protection.json - Ruleset configuration for main branch
• .github/rulesets/integration-branch-protection.json - Ruleset configuration for integration branch
• .ai/docs/strategies/protect-github-repo.md - Strategy documentation

Refactoring

• Built-in Functions: Replaced shell patterns with just built-ins:

  • justfile_directory() instead of $(dirname "$0")
  • justfile() for self-modification
  • path_exists() for file/directory validation
  • error() for clean error handling

• Global Variables:

  • Added target_repo - set via init or override per-command
  • Added justfile_dir, labels_file, rulesets_dir, bundles_dir path variables

• Validation Helpers:

  • _require-repo - Ensures repo parameter is set
  • _require-file - Ensures file exists
  • _require-dir - Ensures directory exists

• Code Cleanup:

  • Removed redundant echo "" statements
  • Removed unnecessary shell variable assignments
  • Marked internal recipes with [private]
  • Simplified heredocs to inline strings

Protection Rules Applied

Main Branch

• ❌ Direct pushes blocked
• ❌ Force pushes blocked
• ❌ Branch deletion blocked
• ✅ Requires 1 PR review
• ✅ Dismisses stale reviews
• ✅ Requires conversation resolution
• ✅ Requires linear history

Integration Branch

• ❌ Direct pushes blocked
• ❌ Force pushes blocked
• ❌ Branch deletion blocked
• ✅ Requires 1 PR review
• ✅ Dismisses stale reviews
• ✅ Requires conversation resolution

Usage

# First-time setup
just init

# After init, no need to specify repo
just protect-repo
just list-rulesets
just sync-labels

# Or override the default
just protect-repo other-owner/other-repo

# Apply a custom ruleset
just apply-ruleset path/to/custom-ruleset.json

Commits

1. feat(just): Adding justfile entries for protecting repository
2. docs(just): Documenting justfile entries for protecting repository
3. refactor(just): Use built-in functions, add init recipe, and target_repo default