v0.7.13

Fixes

• Single-model --models flag: --models "x-ai/grok-4-fast" now correctly overrides the model for all providers. Previously only multi-model (>1) was handled; a single model was silently ignored.
• Stale OpenRouter default: Updated from retired qwen/qwen3.6-plus-preview:free to qwen/qwen3.6-plus:free