v0.8.20

• Added code_assets 2.x compatibility while retaining support for 1.x native
  asset toolchains.

• Updated the default llama.cpp native runtime pin to
  leehack/llamadart-native@b10514, adding BailingMoE3,
  GraniteSWA/GraniteMoeSWA, speculators-format DSpark checkpoints, and current
  upstream multimodal/backend improvements. Matching Dart FFI bindings and the
  llamadart_llama_cpp_flutter Apple SwiftPM artifact were refreshed.

• Updated the default WebGPU bridge assets to v0.1.37, embedding llama.cpp
  b10514 to restore native/Web parity. The bridge provisions an explicit 1 MiB
  Wasm stack for wasm32 and memory64, preventing Qwen3-ASR memory64 context
  construction from overflowing the default stack.

• Improved Web microphone transcription by warming up browser capture before
  showing the recording-ready state, trimming the warmup silence, and
  rejecting too-short, silent, or unsupported PCM WAV captures before
  inference.

• Added logical batch-size (n_batch) and micro-batch-size (n_ubatch)
  controls for llama.cpp/WebGPU models in the Flutter chat example.

• Improved Android Auto backend selection by probing the packaged Vulkan device
  before memory planning, avoiding unnecessary CPU fallback on capable models.

• Updated the native LiteRT-LM runtime to v0.16.0-native.2. The Apple companion
  packages the iOS Gemma constraint provider and Metal accelerator/sampler
  plugins required by the published runtime.

• Added an experimental SpeechToTextEngine.liteRtLm path with capability
  discovery, worker-isolated CPU inference, bounded mono 16 kHz float PCM,
  partial/final transcript events, finalization, and cancellation.

• Added experimental live dictation to the native Flutter chat example for
  chat models using selectable Moonshine Tiny and Parakeet TDT 0.6B sidecars.
  Live dictation is CPU-only, English-only, capped at five minutes, and
  unavailable on Linux and Web.

• Improved Flutter chat example model downloads with bounded retries for
  transient network failures, safe resume after truncated responses, and a
  distinct integrity-verification state after transfer reaches 100%.

• Redesigned the Flutter chat example onboarding and Lab surfaces, preserved a
  completed model card's viewport position when downloads reorder the catalog,
  and stopped streaming responses from pulling users away from chat history.

• Added an experimental typed TextToSpeechEngine for native llama.cpp and
  WebGPU with Qwen3-TTS models, including capability discovery, speaker
  references, cancellable progress, complete 24 kHz PCM output, and WAV
  encoding. The Flutter chat example adds synthesis, playback, replay, and WAV
  save controls. Apple apps discover the TTS ABI in the embedded llama
  framework; current LiteRT-LM artifacts fail explicitly as unsupported.

• Added an experimental typed SpeechToTextEngine with an explicit Qwen3-ASR
  adapter profile for whole-file llama.cpp transcription. The Flutter chat
  example includes a checksum-pinned Qwen3-ASR 0.6B preset plus file and
  microphone transcription on native and WebGPU. Web accepts WAV bytes only;
  native LiteRT-LM live dictation remains a separate implementation.

• Added Ask with voice to the native Flutter chat example for Gemma 4 E2B
  through LiteRT-LM direct media and audio-capable GGUF + projector paths. It
  sends a microphone recording through multimodal chat and remains separate
  from typed speech-to-text.

• Added experimental, opt-in native llama.cpp DSpark speculative decoding
  through SpeculativeDecodingConfig.draftDspark(...) with a compatible
  external draft model.