Add strongly typed Permissions struct for GitHub Actions permissions

[Copilot]

Plan: Add Strongly Typed Permissions Struct

• Create Permissions struct in pkg/workflow/permissions.go with:
  • Support for shorthand permissions (read-all, write-all, read, write, none)
  • Support for granular permissions map (contents, issues, pull-requests, etc.)
  • Constructor functions for common patterns
  • Merge method to combine permissions (write implies read)
  • RenderToYAML method for rendering to GitHub Actions YAML format
• Add comprehensive unit tests for Permissions struct
  • Add extensive tests for Merge method (36 test cases)
• Replace hardcoded permission strings in workflow package:
  • add_comment.go
  • add_labels.go
  • create_issue.go
  • create_discussion.go
  • create_pr_review_comment.go
  • create_pull_request.go
  • create_code_scanning_alert.go
  • notify_comment.go
  • push_to_pull_request_branch.go
  • publish_assets.go
  • safe_jobs.go
  • threat_detection.go
  • tools.go
  • missing_tool.go
  • compiler.go
• Run tests and validate changes
• Run agent-finish for final validation

Test Coverage for Merge Method

Added 36 comprehensive test cases covering:

Map-to-Map Merges (8 tests)

• Write overriding read
• Read not overriding write
• Different scopes
• Multiple scopes with conflicts
• None permission interactions
• All permission scopes

Shorthand-to-Shorthand Merges (15 tests)

• All combinations: write-all, write, read-all, read, none
• Precedence rules (write-all > write > read-all > read > none)
• Same shorthand preservation

Shorthand-to-Map Merges (5 tests)

• Read-all/write-all adding missing scopes
• Read/write adding missing scopes
• None shorthand (no change)

Map-to-Shorthand Merges (4 tests)

• Converting shorthand to map when merging
• Complex map merges

Edge Cases (4 tests)

• Nil merges
• Empty map merges

All 36 tests pass successfully ✅

Original prompt

Add a strongly typed Permissions struct go type that represents a GitHub actions permissions object.

• support shortcuts like "read-all", ...
• support merging 2 permissions object (write implies read)
• add support for rendering to yaml
• search for instances of "permissions:..." and use helper instead
• locate new code in permissions.go

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[pelikhan]

@copilot add extensive tests for merge

[github-actions]

Agentic Changeset Generator triggered by this pull request.

[Copilot]

@copilot add extensive tests for merge

Added 36 extensive test cases for the Merge method covering:

• Map-to-map merges (8 tests)
• Shorthand-to-shorthand merges (15 tests)
• Shorthand-to-map merges (5 tests)
• Map-to-shorthand merges (4 tests)
• Edge cases with nil and empty maps (4 tests)

All tests validate proper precedence rules (write > read > none) and shorthand conversion behavior. Commit: TBD

@copilot add extensive tests for merge

Added 36 extensive test cases for the Merge method covering:

• Map-to-map merges (8 tests)
• Shorthand-to-shorthand merges (15 tests)
• Shorthand-to-map merges (5 tests)
• Map-to-shorthand merges (4 tests)
• Edge cases with nil and empty maps (4 tests)

All tests validate proper precedence rules (write > read > none) and shorthand conversion behavior. Commit: f31d353