[FEAT/#9]소셜로그인 구현

[starshape7]

📌𝗧𝗮𝘀𝗸

• 네이버 소셜로그인 구현
• 카카오 소셜 로그인 구현

💡𝗥𝗲𝗳𝗲𝗿𝗲𝗻𝗰𝗲

[coderabbitai]

A summary of the changes CodeRabbit can apply:

• Implement Kakao and Naver social login by adding three modules (domain/auth, data/auth, feature/auth) with new files (models, repository interface and impl, API service, DTOs/mappers, Hilt modules, LoginScreen/LoginViewModel/LoginState/LoginNavigation), update SpotApplication for SDK init, AndroidManifest for Kakao redirect, build config/local.properties for API keys, DataStore token storage, navigation start destination, and include documentation files (IMPLEMENTATION_COMPLETE.md, docs/*, local.properties.example).

• Implement Kakao and Naver social login by adding domain:data:feature auth modules (new files: domain/auth/* (models, AuthRepository), data/auth/* (AuthService, DTOs, DataSource/Impl, AuthRepositoryImpl, mapper, DI modules, Retrofit service), feature/auth/* (LoginScreen, LoginViewModel, LoginState, LoginNavigation)), update app/build.gradle.kts and settings.gradle.kts to include and depend on the new modules, add SDK initialization and manifest redirect changes (SpotApplication, AndroidManifest.xml), extend build config and provider for Naver keys (BuildConfig, BuildConfigFields, BuildConfigFieldsProviderImpl), add Naver color to design system (Color.kt), add docs and local.properties.example, and include ProGuard/Gradle module files and minor navigation/main host adjustments.

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