feat(cli): add command alias support

[platinummonkey]

Summary

Implements gh-style command aliases as requested in issue #38. Users can now create shortcuts for frequently used pup commands, stored in ~/.config/pup/config.yml.

Features

Core Commands:

• pup alias set <name> <command> - Create or update an alias
• pup alias list - Display all configured aliases
• pup alias delete <name> - Remove one or more aliases
• pup alias import <file> - Bulk import aliases from YAML file

Smart Features:

• Quote handling: Properly parses commands with single/double quotes
• Additional arguments: Pass extra args when using aliases (e.g., pup my-alias --extra-flag)
• Sorted output: Aliases displayed alphabetically
• Merge imports: Imported aliases merge with existing ones

Security Protections:

• Dual-layer validation prevents aliases from overriding built-in commands
• Runtime check ensures built-in commands always execute first, even if:
  • Alias validation is bypassed (manual config.yml editing)
  • New commands are added after aliases are created
  • Reserved command list becomes out of sync
• Validation rejects reserved command names and invalid characters

Examples

# Create an alias for a complex logs query
pup alias set prod-errors "logs search --query='status:error' --tag='env:prod'"

# Use the alias
pup prod-errors

# Add additional arguments
pup prod-errors --from="1h"

# List all aliases
pup alias list

# Delete an alias
pup alias delete prod-errors

# Import team aliases
pup alias import team-aliases.yml

Implementation

New Files:

• cmd/alias.go - Main alias command with 4 subcommands (270 lines)
• cmd/alias_test.go - Comprehensive command tests (330 lines)
• pkg/config/alias.go - YAML storage/retrieval (160 lines)
• pkg/config/alias_test.go - Config package tests (190 lines)

Modified Files:

• cmd/root.go - Added ExecuteWithArgs() with alias resolution + built-in command protection
• go.mod - Added gopkg.in/yaml.v3 dependency

Testing

• ✅ All existing tests pass
• ✅ New tests: 19 test cases covering:
  • Alias creation, listing, deletion, import
  • Validation (reserved names, invalid characters)
  • Quote parsing and argument expansion
  • Built-in command override protection
  • Edge cases and error handling
• ✅ 100% coverage for config package
• ✅ Full integration tests for cmd package

Test Plan

• Create aliases with pup alias set
• List aliases with pup alias list
• Use aliases as commands
• Pass additional arguments to aliases
• Delete aliases with pup alias delete
• Import aliases from YAML files
• Verify built-in commands cannot be overridden
• Test quote handling in commands
• Verify validation rejects invalid names
• Run full test suite

Related Issues

Closes #38

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🤖 Generated with Claude Code

[github-actions]

📊 Test Coverage Report

Overall Coverage: 81.7%

Threshold: 80% ✅

Coverage by Package

## Coverage by Package

- github.com/DataDog/pup/pkg/auth/callback/server.go:40: 81.2%
- github.com/DataDog/pup/pkg/auth/dcr/client.go:28: 100.0%
- github.com/DataDog/pup/pkg/auth/dcr/types.go:24: 100.0%
- github.com/DataDog/pup/pkg/auth/oauth/client.go:22: 100.0%
- github.com/DataDog/pup/pkg/auth/oauth/pkce.go:24: 85.7%
- github.com/DataDog/pup/pkg/auth/storage/factory.go:53: 94.7%
- github.com/DataDog/pup/pkg/auth/storage/keychain.go:44: 42.9%
- github.com/DataDog/pup/pkg/auth/storage/storage.go:58: 71.4%
- github.com/DataDog/pup/pkg/auth/types/types.go:23: 100.0%
- github.com/DataDog/pup/pkg/client/client.go:32: 94.4%
- github.com/DataDog/pup/pkg/config/alias.go:26: 100.0%
- github.com/DataDog/pup/pkg/config/config.go:22: 100.0%
- github.com/DataDog/pup/pkg/formatter/formatter.go:31: 100.0%
- github.com/DataDog/pup/pkg/useragent/useragent.go:32: 100.0%
- github.com/DataDog/pup/pkg/util/time.go:20: 95.8%

## Summary

total:								(statements)		81.7%

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📈 Coverage Status: ✅ PASSED - Coverage meets minimum threshold

_{Updated for commit 698ce13}