- Providers/GPT-5: move the GPT-5 prompt overlay into the shared provider runtime so compatible GPT-5 models receive the same behavior and heartbeat guidance through OpenAI, OpenRouter, OpenCode, Codex, and other GPT providers; add `agents.defaults.promptOverlays.gpt5.personality` as the global friendly-style toggle while keeping the OpenAI plugin setting as a fallback.

- Providers/xAI: add image generation, text-to-speech, and speech-to-text support, including `grok-imagine-image` / `grok-imagine-image-pro`, reference-image edits, six live xAI voices, MP3/WAV/PCM/G.711 TTS formats, `grok-stt` audio transcription, and xAI realtime transcription for Voice Call streaming. (#68694) Thanks @KateWilkins.

- Providers/STT: add Voice Call streaming transcription for Deepgram, ElevenLabs, and Mistral, and add ElevenLabs Scribe v2 batch audio transcription for inbound media.

- Plugin SDK/realtime transcription: add a shared WebSocket session helper for streaming STT providers, covering queueing, ready handshakes, proxy capture, reconnects, and close flushing without each plugin reimplementing the transport loop.

- Models/commands: add `/models add <provider> <modelId>` so you can register a model from chat and use it without restarting the gateway; keep `/models` as a simple provider browser while adding clearer add guidance and copy-friendly command examples. (#70211) Thanks @Takhoffman.

- Pi/models: update the bundled pi packages to `0.68.1` and let the OpenCode Go catalog come from pi instead of plugin-maintained model aliases, adding the refreshed `opencode-go/kimi-k2.6`, Qwen, GLM, MiMo, and MiniMax entries.

- CLI/doctor plugins: lazy-load doctor plugin paths and prefer installed plugin `dist/*` runtime entries over source-adjacent JavaScript fallbacks, reducing the measured `doctor --non-interactive` runtime by about 74% while keeping cold doctor startup on built plugin artifacts. (#69840) Thanks @gumadeiras.