Fix Modal image build: JS SDK only has dockerfileCommands, not aptInstall/runCommands.

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Co-Authored-By: Indent <noreply@indent.com>

Author: jsegaran

js/demo/src/demo.ts

@@ -170,12 +170,12 @@ export async function handleDemoRequest(
       });
       const image = modal.images
         .fromRegistry("ubuntu:24.04")
-        .aptInstall("curl", "git", "htop", "mpv", "ca-certificates")
-        .runCommands(
-          `curl -fsSL ${BLIT_DEB_URL} -o /tmp/blit.deb && dpkg -i /tmp/blit.deb && rm /tmp/blit.deb`,
-          "curl -fsSL https://opencode.ai/install | bash && ln -sf /root/.opencode/bin/opencode /usr/local/bin/opencode",
-          "mkdir -p /home/blit",
-        );
+        .dockerfileCommands([
+          "RUN apt-get update && apt-get install -y curl git htop mpv ca-certificates && rm -rf /var/lib/apt/lists/*",
+          `RUN curl -fsSL ${BLIT_DEB_URL} -o /tmp/blit.deb && dpkg -i /tmp/blit.deb && rm /tmp/blit.deb`,
+          "RUN curl -fsSL https://opencode.ai/install | bash && ln -sf /root/.opencode/bin/opencode /usr/local/bin/opencode",
+          "RUN mkdir -p /home/blit",
+        ]);
 
       const startupScript = [
         "set -e",