docs: note nix support

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Features
 - Talk mode: continuous speech conversations (macOS/iOS/Android) with ElevenLabs TTS, reply directives, and optional interrupt-on-speech.
 - UI: add optional `ui.seamColor` accent to tint the Talk Mode side bubble (macOS/iOS/Android).
+- Nix mode: opt-in declarative config + read-only settings UI when `CLAWDIS_NIX_MODE=1` (thanks @joshp123 for the persistence — earned my trust; I'll merge these going forward).
 - Agent runtime: accept legacy `Z_AI_API_KEY` for Z.AI provider auth (maps to `ZAI_API_KEY`).
 - Tests: add a Z.AI live test gate for smoke validation when keys are present.
 - macOS Debug: add app log verbosity and rolling file log toggle for swift-log-backed app logs.

README.md

@@ -46,6 +46,7 @@ Your surfaces
 - **Automation-ready** — browser control, media handling, and tool streaming.
 - **Local-first control plane** — the Gateway owns state, everything else connects.
 - **Group chats** — mention-based by default, `/activation always|mention` per group (owner-only).
+- **Nix mode** — opt-in declarative config + read-only UI when `CLAWDIS_NIX_MODE=1`.
 
 ## How it works (short)