docs: credit upstream Qwen3-TTS in NOTICE

docs: honest attribution — base_model Qwen3-TTS-12Hz-1.7B-Base + credit + drop Zen MoDE

Add LICENSE and NOTICE files for license compliance

Add NOTICE: Copyright Zen Authors

Update model card: add zen/zenlm tags, fix branding

Add model weights

Fix voice names (cherry/noah) and add custom voice docs

Update with native Thinker-Talker architecture diagram and full documentation

Upload README.md with huggingface_hub

initial commit