stage-batch34: stamp v0.51.152 / Release DX

Single-PR optional gateway-backed browser chat (nesquena#3021)

Author: nesquena-hermes

CHANGELOG.md

@@ -3,6 +3,12 @@
 
 ## [Unreleased]
 
+## [v0.51.152] — 2026-05-28 — Release DX (stage-batch34 — single-PR optional gateway-backed browser chat)
+
+### Added
+
+- Browser chat can now opt into a default-off `HERMES_WEBUI_CHAT_BACKEND=gateway` bridge that routes new WebUI turns through a running Hermes Gateway API server while preserving the existing WebUI chat start/stream contract. Strict enable: only the literal values `gateway`, `api_server`, or `api-server` activate the bridge — generic truthy strings like `1` or `true` keep the legacy in-process WebUI runtime. Configurable via `HERMES_WEBUI_GATEWAY_BASE_URL` (default `http://127.0.0.1:8642`) and `HERMES_WEBUI_GATEWAY_API_KEY` (falls back to `API_SERVER_KEY`). New `api/gateway_chat.py` module isolates the bridge logic; existing direct WebUI chat path unchanged when the env/config is not set. (#3021)
+
 ## [v0.51.151] — 2026-05-28 — Release DW (stage-batch33 — 3-PR mid-risk batch: SSE reattach + title-lang + composer cap)
 
 ### Fixed