feat(config): add CodingBuddy configuration schema

- Add TypeScript types and Zod validation schema
- Add comprehensive test coverage
- Add configuration documentation

close #23

Author: wishket-pjw

docs/config-schema.md

@@ -0,0 +1,266 @@
+# CodingBuddy Configuration Schema
+
+This document describes the configuration schema for CodingBuddy. The configuration file provides project context to AI assistants without overriding `.ai-rules`.
+
+## Quick Start
+
+Create a `codingbuddy.config.js` file in your project root:
+
+```javascript
+module.exports = {
+  language: 'ko',
+  projectName: 'my-awesome-app',
+  techStack: {
+    frontend: ['React', 'TypeScript'],
+    backend: ['NestJS'],
+  },
+};
+```
+
+## Configuration File Formats
+
+CodingBuddy supports multiple configuration file formats (in priority order):
+
+1. `codingbuddy.config.js` - JavaScript (recommended, supports dynamic values)
+2. `codingbuddy.config.json` - JSON
+3. `.codingbuddyrc` - RC file format
+
+## Schema Reference
+
+### Basic Settings
+
+| Field | Type | Description | Example |
+|-------|------|-------------|---------|
+| `language` | `string` | Response language for AI | `'ko'`, `'en'`, `'ja'` |
+| `projectName` | `string` | Project name | `'my-app'` |
+| `description` | `string` | Project description | `'E-commerce platform'` |
+| `repository` | `string` | Repository URL | `'https://github.com/...'` |
+
+### Tech Stack (`techStack`)
+
+Configure your project's technology stack:
+
+```javascript
+techStack: {
+  // Basic (Nested)
+  languages: ['TypeScript', 'Python'],
+  frontend: ['React', 'Next.js', 'Tailwind CSS'],
+  backend: ['NestJS', 'Express'],
+  database: ['PostgreSQL', 'Redis'],
+  infrastructure: ['Docker', 'AWS', 'Kubernetes'],
+  tools: ['ESLint', 'Prettier', 'Husky'],
+
+  // Deep (Optional) - detailed tech info
+  details: {
+    'TypeScript': {
+      version: '5.x',
+      notes: 'Strict mode enabled'
+    }
+  }
+}
+```
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `languages` | `string[]` | Programming languages |
+| `frontend` | `string[]` | Frontend frameworks/libraries |
+| `backend` | `string[]` | Backend frameworks/libraries |
+| `database` | `string[]` | Databases and data stores |
+| `infrastructure` | `string[]` | Infrastructure/DevOps tools |
+| `tools` | `string[]` | Development tools |
+| `details` | `Record<string, TechDetail>` | (Deep) Detailed tech info |
+
+### Architecture (`architecture`)
+
+Define your project's architecture:
+
+```javascript
+architecture: {
+  // Basic (Nested)
+  pattern: 'feature-sliced',
+  structure: ['src/', 'app/', 'features/', 'entities/', 'shared/'],
+  componentStyle: 'feature-based',
+
+  // Deep (Optional) - layer definitions
+  layers: [
+    { name: 'app', path: 'src/app', description: 'Application layer' },
+    { name: 'features', path: 'src/features', dependencies: ['entities', 'shared'] }
+  ]
+}
+```
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `pattern` | `string` | Architecture pattern (`'layered'`, `'hexagonal'`, `'clean'`, `'feature-sliced'`, etc.) |
+| `structure` | `string[]` | Key directory paths |
+| `componentStyle` | `string` | Component organization (`'flat'`, `'grouped'`, `'feature-based'`) |
+| `layers` | `ArchitectureLayer[]` | (Deep) Layer definitions |
+
+### Conventions (`conventions`)
+
+Specify coding conventions:
+
+```javascript
+conventions: {
+  // Basic (Nested)
+  style: 'airbnb',
+  naming: {
+    files: 'kebab-case',
+    components: 'PascalCase',
+    functions: 'camelCase',
+    variables: 'camelCase',
+    constants: 'UPPER_SNAKE_CASE'
+  },
+  importOrder: ['react', '@/', '~/', '.'],
+  maxLineLength: 100,
+  semicolons: true,
+  quotes: 'single',
+
+  // Deep (Optional) - custom rules
+  rules: {
+    'no-console': 'warn'
+  }
+}
+```
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `style` | `string` | Style guide (`'airbnb'`, `'google'`, `'standard'`, `'prettier'`) |
+| `naming` | `NamingConvention` | Naming convention rules |
+| `importOrder` | `string[]` | Import ordering preference |
+| `maxLineLength` | `number` | Maximum line length |
+| `semicolons` | `boolean` | Use semicolons |
+| `quotes` | `string` | Quote style (`'single'`, `'double'`) |
+| `rules` | `Record<string, unknown>` | (Deep) Custom linting rules |
+
+### Test Strategy (`testStrategy`)
+
+Configure testing approach:
+
+```javascript
+testStrategy: {
+  approach: 'tdd',
+  frameworks: ['vitest', 'playwright'],
+  coverage: 80,
+  unitTestPattern: 'colocated',
+  e2eDirectory: 'e2e/',
+  mockingStrategy: 'minimal'
+}
+```
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `approach` | `string` | Testing approach (`'tdd'`, `'bdd'`, `'test-after'`, `'mixed'`) |
+| `frameworks` | `string[]` | Test frameworks |
+| `coverage` | `number` | Target coverage percentage (0-100) |
+| `unitTestPattern` | `string` | Unit test location (`'colocated'`, `'separate'`) |
+| `e2eDirectory` | `string` | E2E test directory |
+| `mockingStrategy` | `string` | Mocking approach (`'minimal'`, `'extensive'`, `'no-mocks'`) |
+
+### Additional Context
+
+```javascript
+// Key files AI should be aware of
+keyFiles: [
+  'src/core/types.ts',
+  'docs/architecture.md',
+  'CONTRIBUTING.md'
+],
+
+// Topics or areas to avoid
+avoid: [
+  'legacy-api',
+  'deprecated-module'
+],
+
+// Custom freeform context
+custom: {
+  team: 'Platform Team',
+  domain: 'E-commerce'
+}
+```
+
+## Complete Example
+
+```javascript
+// codingbuddy.config.js
+module.exports = {
+  // Basic
+  language: 'ko',
+  projectName: 'wishket-platform',
+  description: 'Freelancer marketplace platform',
+  repository: 'https://github.com/example/wishket-platform',
+
+  // Tech Stack
+  techStack: {
+    languages: ['TypeScript'],
+    frontend: ['React', 'Next.js', 'Tailwind CSS', 'React Query'],
+    backend: ['NestJS', 'TypeORM'],
+    database: ['PostgreSQL', 'Redis'],
+    infrastructure: ['Docker', 'AWS ECS', 'GitHub Actions'],
+  },
+
+  // Architecture
+  architecture: {
+    pattern: 'feature-sliced',
+    structure: ['src/app', 'src/features', 'src/entities', 'src/shared'],
+    componentStyle: 'feature-based',
+  },
+
+  // Conventions
+  conventions: {
+    style: 'airbnb',
+    naming: {
+      files: 'kebab-case',
+      components: 'PascalCase',
+      functions: 'camelCase',
+    },
+    quotes: 'single',
+    semicolons: true,
+  },
+
+  // Test Strategy
+  testStrategy: {
+    approach: 'tdd',
+    frameworks: ['vitest', 'playwright'],
+    coverage: 80,
+    unitTestPattern: 'colocated',
+    mockingStrategy: 'minimal',
+  },
+
+  // Additional
+  keyFiles: ['src/shared/types/index.ts', 'docs/api.md'],
+  avoid: ['legacy-v1-api'],
+};
+```
+
+## TypeScript Types
+
+Import types for type-safe configuration:
+
+```typescript
+import type { CodingBuddyConfig } from 'codingbuddy/config';
+
+const config: CodingBuddyConfig = {
+  language: 'en',
+  // ... IDE autocomplete works here
+};
+
+module.exports = config;
+```
+
+## Validation
+
+The configuration is validated at runtime using Zod schemas. Invalid configurations will produce clear error messages:
+
+```
+Error: Invalid configuration
+  - techStack.coverage: Expected number, received string
+  - conventions.quotes: Invalid enum value. Expected 'single' | 'double'
+```
+
+## Notes
+
+- **All fields are optional** - start with what you need
+- **No rule override** - this config provides context only; `.ai-rules` rules remain unchanged
+- **AI context only** - this information helps AI understand your project better