feat: add multi-profile credential support

[Palbahngmiyine]

Summary

• nurigo/solapi-crm-core CLI와 동일한 멀티 프로필 credential 옵션 지원 추가
• --profile persistent flag, configure list/use/delete 서브커맨드 구현
• 기존 flat format({api_key, api_secret}) → 멀티프로필 format 자동 마이그레이션 (하위 호환)

Changes

New files

• cmd/configure_list.go — solactl configure list 프로필 목록 표시
• cmd/configure_use.go — solactl configure use <profile> 활성 프로필 전환
• cmd/configure_delete.go — solactl configure delete <profile> 프로필 삭제

Modified files

• pkg/config/config.go — CredentialsFile, LoadOptions, ProfileInfo 구조체 추가, Load/Save 시그니처 변경, 프로필 관리 함수(SetActiveProfile, DeleteProfile, ListProfiles, ActiveProfileName), detectAndLoad 하위 호환 마이그레이션
• cmd/root.go — --profile persistent flag 추가, loadConfig() → LoadOptions 사용
• cmd/configure.go — 프로필 인식 runConfigure/saveConfigure, 진단 메시지 errOut() 준수
• cmd/configure_show.go — Profile 이름 표시, LoadOptions 전달
• pkg/config/config_test.go — 기존 테스트 시그니처 업데이트 + 신규 프로필 테스트 20개 + fuzz 테스트
• cmd/configure_test.go — 신규 서브커맨드 테스트 12개

Test plan

• go build ./... 컴파일 성공
• go test ./... 전체 테스트 통과
• go test -race ./... race condition 없음
• go vet ./... 경고 없음
• solactl configure --profile staging --api-key K --api-secret S 프로필 저장
• solactl configure list 프로필 목록 확인
• solactl configure use staging 활성 프로필 전환
• solactl configure delete staging 프로필 삭제
• old format 파일 → solactl configure show 자동 마이그레이션 확인

🤖 Generated with Claude Code

[gemini-code-assist]

Code Review

This pull request introduces multi-profile support for the CLI configuration, allowing users to manage multiple sets of API credentials. Key changes include the addition of list, use, and delete subcommands under configure, a new persistent --profile flag, and an updated storage format in credentials.json that maintains backward compatibility with the previous flat structure. Feedback focuses on strengthening error handling: specifically, preventing potential data loss in the Save function when the configuration file is corrupted and improving the specificity of error messages in the list command to distinguish between a missing file and other I/O or parsing errors.

[gemini-code-assist]

The error from loadCredentialsFile() is being ignored. If the credentials file exists but is corrupted (e.g., invalid JSON), loadCredentialsFile() will return an error and a nil configuration. By ignoring this error, the Save function will proceed to initialize a fresh CredentialsFile and overwrite the existing file, potentially causing data loss of all other stored profiles. You should check if the error is something other than 'file not found' before proceeding.

Suggested change

	cf, _ := loadCredentialsFile()
	cf, err := loadCredentialsFile()
	if err != nil && !os.IsNotExist(err) {
	return fmt.Errorf("설정 파일 로드 실패: %w", err)
	}

[gemini-code-assist]

The os package needs to be imported to check for file existence errors using os.IsNotExist.

Suggested change

	"fmt"
	"fmt"
	"os"

[gemini-code-assist]

The current implementation swallows all errors from config.ListProfiles() and provides a generic "No profiles" message. If the configuration file is corrupted or unreadable due to permission issues, this message is misleading and the command incorrectly returns a success exit code (0). It is better to specifically check for the 'file not found' case and return other errors to the caller.

if err != nil {
	if os.IsNotExist(err) {
		_, _ = fmt.Fprintf(errOut(), "프로필이 없습니다. 'solactl configure'를 실행하세요.\n")
		return nil
	}
	return err
}