fix: keep python3 runtime, verify native binding path, selective cleanup

apk del python3 cascades to remove sqlite-libs. Only remove make/g++.
Add debug step to verify better_sqlite3.node was built.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Dockerfile

@@ -4,9 +4,12 @@ WORKDIR /app
 RUN corepack enable pnpm
 COPY package.json pnpm-lock.yaml ./
 RUN pnpm install --frozen-lockfile
+# Verify native binding was built
+RUN find node_modules -name "better_sqlite3.node" -ls
 COPY . .
 RUN pnpm run build
-RUN apk del python3 make g++ && rm -rf /root/.cache /tmp/*
+# Keep only build tools cleanup that won't remove sqlite-libs
+RUN apk del make g++ && rm -rf /root/.cache /tmp/*
 RUN mkdir -p /data && chown node:node /data
 USER node
 ENV NODE_ENV=production