star config should be a builtin command #337

Migrated from NobleFactor/noblefactor-ops#40 (star now lives in this repository; GitHub blocks private→public transfers). Original discussion remains there.

Summary

The star config command should be implemented as a builtin command rather than an extension.

Context

Currently config.show and config.sync are implemented as extensions in extensions/config-show/ and extensions/config-sync/. These should be builtin commands since they deal with core star configuration functionality.

Current State

• extensions/config-show/ - shows merged configuration
• extensions/config-sync/ - syncs tool configs from star.yaml

Proposed Structure

star config
├── show    - Show merged configuration from star.yaml hierarchy
└── sync    - Sync tool configs (.golangci.yaml, etc.) from star.yaml

Rationale

Configuration management is core functionality that should be available even without extensions loaded. Builtin commands provide:

• Faster startup (no extension discovery needed)
• Always available regardless of extension search paths
• Consistent with self command pattern

Epic: #441 · Feature: #456