# Task 0.2.2: Create Config Interface

## Metadata
- **Task ID**: 0.2.2
- **Title**: Create Config Interface
- **Phase**: 0 - Project Setup & Foundation
- **Section**: 0.2 Configuration System
- **Status**: Pending
- **Priority**: High
- **Estimated Time**: 15 minutes
- **Dependencies**: 0.2.1

## Description
Create the `ConfigProvider` interface in `pkg/config/` to abstract configuration access. This interface will be used by all modules and services.

## Requirements
- Define interface in `pkg/config/config.go`
- Include methods for type-safe access
- Support nested configuration keys
- Support unmarshaling into structs

## Implementation Steps
1. Create `pkg/config/config.go`
2. Define `ConfigProvider` interface:
   ```go
   type ConfigProvider interface {
       Get(key string) any
       Unmarshal(v any) error
       GetString(key string) string
       GetInt(key string) int
       GetBool(key string) bool
       GetStringSlice(key string) []string
   }
   ```
3. Add package documentation
4. Export interface for use by modules

## Acceptance Criteria
- [ ] `pkg/config/config.go` exists
- [ ] `ConfigProvider` interface is defined
- [ ] Interface methods match requirements
- [ ] Package documentation is present
- [ ] Interface compiles without errors

## Related ADRs
- [ADR-0004: Configuration Management](../../adr/0004-configuration-management.md)

## Implementation Notes
- Interface should be minimal and focused
- Additional methods can be added later if needed
- Consider adding `GetDuration()` for time.Duration values
- Consider adding `IsSet(key string) bool` to check if key exists

## Testing
```bash
go build ./pkg/config
go vet ./pkg/config
```