fix(ci):overhaul the dash build

apps/start/Dockerfile

@@ -39,16 +39,51 @@ COPY patches ./patches
 # Copy tracking script to self-hosting dashboard
 COPY apps/public/public/op1.js ./apps/start/public/op1.js
 
-# BUILD - run natively on the CI runner to avoid QEMU crashes (esbuild Go runtime)
+# BASE-BUILD - native platform image so the build step runs without QEMU.
-FROM --platform=$BUILDPLATFORM base AS build
+# "FROM --platform=$BUILDPLATFORM base AS build" alone is not enough because
+# `base` has no --platform override, so Docker resolves it from the target-platform
+# cache (linux/amd64) and the build stage still runs under QEMU emulation on ARM64
+# runners, causing esbuild's Go runtime to crash.
+FROM --platform=$BUILDPLATFORM node:${NODE_VERSION}-slim AS base-build
 
-RUN apt-get update && apt-get install -y --no-install-recommends \
+ENV COREPACK_INTEGRITY_KEYS=0
+
+RUN rm -f /usr/local/bin/pnpm /usr/local/bin/pnpx && npm install -g pnpm@10.6.2 && apt-get update && \
+    apt-get install -y --no-install-recommends \
+    ca-certificates \
+    openssl \
+    libssl3 \
+    curl \
     python3 \
     make \
-    g++ && \
+    g++ \
-    apt-get clean && \
+    && apt-get clean && \
     rm -rf /var/lib/apt/lists/*
 
+ENV NITRO=1
+ENV SELF_HOSTED=1
+ENV PNPM_HOME="/pnpm"
+ENV PATH="$PNPM_HOME:$PATH"
+
+WORKDIR /app
+
+COPY package.json pnpm-lock.yaml pnpm-workspace.yaml ./
+COPY apps/start/package.json ./apps/start/
+COPY packages/trpc/package.json packages/trpc/
+COPY packages/json/package.json packages/json/
+COPY packages/common/package.json packages/common/
+COPY packages/importer/package.json packages/importer/
+COPY packages/payments/package.json packages/payments/
+COPY packages/constants/package.json packages/constants/
+COPY packages/validation/package.json packages/validation/
+COPY packages/integrations/package.json packages/integrations/
+COPY packages/sdks/_info/package.json packages/sdks/_info/
+COPY patches ./patches
+COPY apps/public/public/op1.js ./apps/start/public/op1.js
+
+# BUILD - inherits from base-build (native runner platform) so esbuild runs without QEMU
+FROM --platform=$BUILDPLATFORM base-build AS build
+
 WORKDIR /app
 
 # Install all dependencies (including dev dependencies for build)