Fix wmill CLI installation for multi-architecture support

Replace direct binary download with npm-based installation to properly
support both amd64 and arm64 architectures.

Changes:
- Install Node.js 20 via NodeSource repository
- Install windmill-cli globally via npm
- Remove architecture-specific binary download logic that was failing
  because wmill binaries are not published separately from windmill server

This fixes the "Exec format error" that occurred when attempting to run
the wmill CLI on ARM64 systems.

Dockerfile

@@ -2,15 +2,16 @@ FROM python:3.11-slim
 
 WORKDIR /app
 
-# Install system dependencies
+# Install system dependencies including Node.js
 RUN apt-get update && apt-get install -y \
     git \
     curl \
+    && curl -fsSL https://deb.nodesource.com/setup_20.x | bash - \
+    && apt-get install -y nodejs \
     && rm -rf /var/lib/apt/lists/*
 
-# Install wmill CLI
-RUN curl -L https://github.com/windmill-labs/windmill/releases/latest/download/wmill-linux-amd64 -o /usr/local/bin/wmill \
-    && chmod +x /usr/local/bin/wmill
+# Install wmill CLI via npm
+RUN npm install -g windmill-cli
 
 # Copy requirements and install Python dependencies
 COPY requirements.txt .