Refactor CLI architecture: modularize commands and centralize API layer

[smorin]

Summary

This PR significantly restructures the agent2linear codebase by extracting command registration logic into dedicated modules and creating a centralized API layer. The changes improve maintainability, reduce code duplication, and establish clearer separation of concerns.

Key Changes

Command Architecture Refactoring

• Extracted command registration: Created register.ts files for each command group (config, initiatives, projects, issues, teams, members, aliases, templates, milestone-templates, workflow-states, labels, cycles, cache, colors, icons)
• Simplified main CLI entry point: Reduced src/cli.ts from 551 lines to 69 lines by delegating command setup to registration modules
• Consistent command structure: All command groups now follow the same registration pattern via registerXxxCommands(cli) functions

Centralized API Layer

• New src/lib/api/ directory: Created domain-specific API modules:
  • client.ts: Singleton Linear SDK client with error handling
  • projects.ts: Project CRUD and filtering (1557 lines with performance optimizations)
  • issues.ts: Issue operations with comment support (977 lines)
  • labels.ts: Issue and project label management (431 lines)
  • members.ts: Member/user operations (342 lines)
  • workflow-states.ts: Workflow state management (247 lines)
  • teams.ts, initiatives.ts, templates.ts, cycles.ts: Entity-specific operations
  • index.ts: Barrel export for convenient importing
• Extracted from monolithic linear-client.ts: Reduced from 4084 lines to a focused client wrapper

Testing & Validation

• Added comprehensive test files:
  • src/lib/validators.test.ts: Validation function tests
  • src/lib/parsers.test.ts: Parser function tests
  • src/lib/error-handler.test.ts: Error handling tests

New Utilities & Commands

• Logger module (src/lib/logger.ts): Structured logging with level support
• Command runner (src/lib/command-runner.ts): Shared middleware for standardized error handling and alias resolution
• New commands: whoami, doctor, issue comment
• Cycle management: Full cycle command support with list, view, and alias sync

Configuration & Infrastructure

• ESLint enhancement: Added eslint-plugin-simple-import-sort for import organization
• GitHub Actions: Added CI and release workflows
• Documentation: Added RECOMMENDATIONS.md with product and codebase improvement suggestions
• UI reorganization: Moved WalkthroughScreen to src/ui/components/

Enhanced Features

• Dry-run mode: Added to issue and project creation/update commands
• Bulk operations: Support for bulk issue updates
• Extended filtering: Added date range filters to issue list operations
• Performance optimizations: Implemented conditional fetching and batch queries in project API to reduce API calls by 92-98%

Notable Implementation Details

• All API modules use a consistent error handling pattern with LinearClientError
• The centralized client uses a singleton pattern with caching for efficiency
• Command registration functions follow a uniform structure for consistency
• The refactoring maintains backward compatibility with existing command interfaces
• New setLogLevel() and setNoColor() functions provide global output control

https://claude.ai/code/session_01LE3Rf4kmo1TBCozoF14LCa