Fix(docker): optimize pnpm build and explicitly set image tag

- Update Dockerfile:
  - Add `package-import-method copy` to pnpm config to resolve EAGAIN errors during build.
  - Optimize pnpm network concurrency settings.
- Update docker-compose.yml:
  - Explicitly set `image: hotwa/bttoxin-app:latest` for services.

Co-Authored-By: Claude <noreply@anthropic.com>

docker/dockerfiles/Dockerfile.traefik

@@ -28,32 +28,38 @@ RUN pixi shell-hook -e webbackend > /shell-hook.sh && \
 # ===========================
 # Stage 2: Frontend Builder
 # ===========================
-FROM docker.m.daocloud.io/library/node:20 AS frontend-builder
+FROM node:20 AS frontend-builder
 WORKDIR /app
 ENV CI=true
 
-# Copy only frontend source
+# Optimization: Copy package files first to leverage Docker cache
+COPY frontend/package.json frontend/pnpm-lock.yaml* ./
+
+# Optimization: Limit concurrency to avoid EAGAIN errors
+RUN npm install -g pnpm && \
+    pnpm config set registry https://registry.npmmirror.com && \
+    pnpm config set network-concurrency 1 && \
+    pnpm config set package-import-method copy && \
+    pnpm install --no-frozen-lockfile
+
+# Copy remaining source code
 COPY frontend/ .
 
-RUN npm install -g pnpm && \
-    pnpm install --no-frozen-lockfile && \
-    pnpm build
+RUN pnpm build
 
 # ===========================
 # Stage 3: Production (Runtime)
 # ===========================
-FROM docker.m.daocloud.io/library/ubuntu:20.04 AS production
+FROM ghcr.io/prefix-dev/pixi:latest AS production
 WORKDIR /app
 
 # Install runtime dependencies
-RUN apt-get update && apt-get install -y --no-install-recommends \
+RUN apt-get clean && \
+    apt-get update -o Acquire::CompressionTypes::Order::=gz -o Acquire::http::No-Cache=True -o Acquire::http::Pipeline-Depth=0 && \
+    apt-get install -y --no-install-recommends \
     curl \
     && rm -rf /var/lib/apt/lists/*
 
-# Copy pixi executable
-COPY --from=builder /usr/local/bin/pixi /usr/local/bin/pixi
-RUN chmod +x /usr/local/bin/pixi
-
 # Copy entire prepared application directory (Code + Environment + Data)
 COPY --from=builder /app /app