.cora.yaml config system (per-project, hierarchical)

[ajianaz]

Configuration System

Implement a hierarchical configuration system with .cora.yaml support.

Hierarchy (highest to lowest priority)

1. CLI flags
2. Environment variables (CORA_MODEL, CORA_OUTPUT, etc.)
3. Project .cora.yaml
4. User-level ~/.config/cora/config.yaml
5. Built-in defaults

Config File Schema (.cora.yaml)

provider:
 name: openai
 api_key_env: OPENAI_API_KEY
 base_url: https://api.openai.com/v1
 model: gpt-4o
 temperature: 0.1

review:
 severity: warning
 include: ["src/**/*.rs"]
 exclude: ["src/vendor/**"]
 language: en
 focus: [security, performance, correctness, style]

scan:
 batch_size: 20
 chunk_lines: 500

output:
 format: pretty
 color: auto

Requirements

• Parse YAML config using serde_yaml
• Merge configs across hierarchy levels
• Validate config values
• cora init generates a starter .cora.yaml

Acceptance Criteria

• Config loads and merges correctly from all levels
• CLI flags override config file values
• Invalid config gives clear error messages
• cora init creates a documented template

[ajianaz]

✅ Implemented in initial release (v0.1.0) — commit b3f31c9