diff --git a/frontend/AGENTS.md b/frontend/AGENTS.md
index 618d2158..0aad01bf 100644
--- a/frontend/AGENTS.md
+++ b/frontend/AGENTS.md
@@ -76,6 +76,12 @@ src/
 - **MagicUI** - Magic UI components
 - **React Bits** - React bits components
 
+### Interaction Ownership
+
+- `src/app/workspace/chats/[thread_id]/page.tsx` owns composer busy-state wiring.
+- `src/core/threads/hooks.ts` owns pre-submit upload state and thread submission.
+- `src/hooks/usePoseStream.ts` is a passive store selector; global WebSocket lifecycle stays in `App.tsx`.
+
 ## Resources
 
 - [LangGraph Documentation](https://langchain-ai.github.io/langgraph/)
diff --git a/frontend/Dockerfile b/frontend/Dockerfile
index 941945fd..9f37b4ec 100644
--- a/frontend/Dockerfile
+++ b/frontend/Dockerfile
@@ -1,22 +1,49 @@
-# Frontend Development Dockerfile
-FROM node:22-alpine
+# Frontend Dockerfile
+# Supports two targets:
+#   --target dev   — install deps only, run `pnpm dev` at container start
+#   --target prod  — full build baked in, run `pnpm start` at container start (default if no --target is specified)
 
-# Accept build argument for pnpm store path
 ARG PNPM_STORE_PATH=/root/.local/share/pnpm/store
 
-# Install pnpm at specific version (matching package.json)
-RUN corepack enable && corepack install -g pnpm@10.26.2
-
+# ── Base: shared setup ────────────────────────────────────────────────────────
+FROM node:22-alpine AS base
+ARG PNPM_STORE_PATH
+ARG NPM_REGISTRY
+# Configure corepack registry before installing pnpm so the download itself
+# succeeds in restricted networks (COREPACK_NPM_REGISTRY controls where
+# corepack fetches package managers from).
+RUN if [ -n "${NPM_REGISTRY}" ]; then \
+      export COREPACK_NPM_REGISTRY="${NPM_REGISTRY}"; \
+    fi && \
+    corepack enable && corepack install -g pnpm@10.26.2
 RUN pnpm config set store-dir ${PNPM_STORE_PATH}
-
-# Set working directory
+# Optionally override npm registry for restricted networks (e.g. NPM_REGISTRY=https://registry.npmmirror.com)
+RUN if [ -n "${NPM_REGISTRY}" ]; then pnpm config set registry "${NPM_REGISTRY}"; fi
 WORKDIR /app
-
-# Copy frontend source code
 COPY frontend ./frontend
 
-# Install dependencies
-RUN sh -c "cd /app/frontend && pnpm install --frozen-lockfile"
-
-# Expose Next.js dev server port
+# ── Dev: install only, CMD is overridden by docker-compose ───────────────────
+FROM base AS dev
+RUN cd /app/frontend && pnpm install --frozen-lockfile
 EXPOSE 3000
+
+# ── Builder: install + compile Next.js ───────────────────────────────────────
+FROM base AS builder
+RUN cd /app/frontend && pnpm install --frozen-lockfile
+# Skip env validation — runtime vars are injected by nginx/container
+RUN cd /app/frontend && SKIP_ENV_VALIDATION=1 pnpm build
+
+# ── Prod: minimal runtime with pre-built output ───────────────────────────────
+FROM node:22-alpine AS prod
+ARG PNPM_STORE_PATH
+ARG NPM_REGISTRY
+RUN if [ -n "${NPM_REGISTRY}" ]; then \
+      export COREPACK_NPM_REGISTRY="${NPM_REGISTRY}"; \
+    fi && \
+    corepack enable && corepack install -g pnpm@10.26.2
+RUN pnpm config set store-dir ${PNPM_STORE_PATH}
+RUN if [ -n "${NPM_REGISTRY}" ]; then pnpm config set registry "${NPM_REGISTRY}"; fi
+WORKDIR /app
+COPY --from=builder /app/frontend ./frontend
+EXPOSE 3000
+CMD ["sh", "-c", "cd /app/frontend && pnpm start"]