Fix Prisma engine generation by copying schema before npm install

The previous attempt failed because Prisma CLI couldn't parse the binaryTarget
configuration due to an incorrect environment variable I set. This commit:

- Removes the non-existent PRISMA_CLI_BINARY_TARGETS environment variable
- Copies the Prisma schema BEFORE running npm ci, allowing the postinstall
  script to properly generate the Prisma client with engines
- Adds openssl and ca-certificates to deps stage for engine downloads
- Simplifies the builder stage to rely on pre-generated engines from deps

This ensures Prisma engines are downloaded during npm installation via the
postinstall hook, making them available for subsequent build steps.

docker/web/Dockerfile

@@ -12,14 +12,10 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     openssl \
     ca-certificates \
     && rm -rf /var/lib/apt/lists/*
-# Set Prisma to download engines during install and ignore checksum errors
-ENV PRISMA_CLI_BINARY_TARGETS=native,debian-openssl-3.0.x
-ENV PRISMA_ENGINES_CHECKSUM_IGNORE_MISSING=1
 COPY package.json package-lock.json* ./
-RUN if [ -f package-lock.json ]; then npm ci; else npm install; fi
-# Explicitly generate Prisma client with engines during deps stage
+# Copy prisma schema before npm ci so postinstall can generate if needed
 COPY prisma ./prisma
-RUN npx prisma generate
+RUN if [ -f package-lock.json ]; then npm ci; else npm install; fi
 
 FROM base AS builder
 ENV NODE_ENV=production
@@ -27,9 +23,6 @@ ENV NEXT_TELEMETRY_DISABLED=1
 # Set a temporary database path for build
 ENV DATABASE_PATH=/tmp/build.db
 ENV DATABASE_URL=file:/tmp/build.db
-# Skip Prisma engine checksum validation and downloads (engines already bundled from deps stage)
-ENV PRISMA_ENGINES_CHECKSUM_IGNORE_MISSING=1
-ENV PRISMA_SKIP_POSTINSTALL_GENERATE=1
 # Install openssl for Prisma query engine
 RUN apt-get update && apt-get install -y --no-install-recommends \
     openssl \
@@ -37,6 +30,7 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
 COPY --from=deps /app/node_modules ./node_modules
 COPY . .
 # Build the application (prisma client already generated in deps stage with engines)
+# Use db push to create schema without regenerating client
 RUN npx prisma db push --skip-generate
 RUN npm run build && rm -f /tmp/build.db