feat: add PostgreSQL persistence for permanent shareable links

- Add PostgreSQL service to docker-compose with health checks
- Add migrate service that runs prisma migrate deploy on startup
- Integrate Prisma client in worker: checks for existing generations
  (same repo+commit) before regenerating, writes to Postgres on completion
- Update /api/docs/[id] with Redis → PostgreSQL fallback + cache repopulation
- Update Dockerfile: prisma generate in build, copy Prisma engine to worker/web
- Add @codeboard/database dependency to web and worker packages
- Add initial SQL migration for Generation and User tables
- Change removeOnComplete to { age: 3600 } for job retention

Dockerfile

@@ -16,6 +16,7 @@ RUN npm install --production=false
 FROM base AS builder
 COPY --from=deps /app/node_modules ./node_modules
 COPY . .
+RUN npx prisma generate --schema=packages/database/prisma/schema.prisma
 RUN npx turbo build
 
 FROM base AS web
@@ -24,6 +25,7 @@ RUN addgroup --system --gid 1001 nodejs && \
 COPY --from=builder --chown=nextjs:nodejs /app/apps/web/.next/standalone ./
 COPY --from=builder --chown=nextjs:nodejs /app/apps/web/.next/static ./apps/web/.next/static
 COPY --from=builder --chown=nextjs:nodejs /app/apps/web/public ./apps/web/public
+COPY --from=builder --chown=nextjs:nodejs /app/packages/database/prisma ./packages/database/prisma
 USER nextjs
 EXPOSE 3000
 ENV PORT=3000 HOSTNAME="0.0.0.0"
@@ -38,6 +40,10 @@ COPY --from=builder /app/packages/shared/dist ./packages/shared/dist
 COPY --from=builder /app/packages/parser/dist ./packages/parser/dist
 COPY --from=builder /app/packages/llm/dist ./packages/llm/dist
 COPY --from=builder /app/packages/diagrams/dist ./packages/diagrams/dist
+COPY --from=builder /app/packages/database/package.json ./packages/database/
+COPY --from=builder /app/node_modules/.prisma ./node_modules/.prisma
+COPY --from=builder /app/node_modules/@prisma ./node_modules/@prisma
+COPY --from=builder /app/packages/database/prisma ./packages/database/prisma
 COPY --from=builder /app/package.json ./
 COPY --from=builder /app/apps/worker/package.json ./apps/worker/
 COPY --from=builder /app/packages/shared/package.json ./packages/shared/