refactor: streamline evidence generation in coach summary; enhance JSON output contract and improve tokenization handling for local chat

chore: add ninja-build and build-essential to package requirements; update README and documentation to reflect changes in model configuration and local Transformers usage

refactor: update artifact URLs and improve router device handling for better classification performance

feat: add support for local Transformers inference on Hugging Face Spaces with opt-in configuration

docs: update default coach-summary model to build-small-hackathon/pozify-coach-summary1 and clarify fallback behavior in documentation

feat: expand coach summary training pipeline

feat: add coach summary LoRA config and provider plumbing