fix(orchestrator): symlink prisma schema for cross-env generate

Create apps/orchestrator/prisma/schema.prisma as a symlink pointing to
../../api/prisma/schema.prisma. This gives the orchestrator 'ownership'
of its local schema copy so Prisma does not traverse into the api package
looking for project-root context.

- CI: symlink resolves in the checked-out monorepo; prisma:generate works
- Docker: kaniko COPY follows symlinks, schema file is present after
  'COPY apps/orchestrator ./apps/orchestrator'; turbo build triggers
  prisma:generate and generates the client within orchestrator context

Revert prisma:generate script to canonical path (./prisma/schema.prisma).
Remove deprecated 'prisma' config key from package.json.
Simplify Dockerfile builder stage (no more manual generate RUN).

apps/orchestrator/Dockerfile

@@ -21,9 +21,7 @@ FROM base AS deps
 COPY packages/shared/package.json ./packages/shared/
 COPY packages/config/package.json ./packages/config/
 COPY apps/orchestrator/package.json ./apps/orchestrator/
-# Copy API package.json + prisma schema so prisma generate can find the project root
-COPY apps/api/package.json ./apps/api/package.json
-COPY apps/api/prisma ./apps/api/prisma
+# API schema is available via apps/orchestrator/prisma/schema.prisma symlink
 
 # Copy npm configuration for native binary architecture hints
 COPY .npmrc ./
@@ -49,10 +47,11 @@ COPY --from=deps /app/packages/shared/node_modules ./packages/shared/node_module
 COPY --from=deps /app/packages/config/node_modules ./packages/config/node_modules
 COPY --from=deps /app/apps/orchestrator/node_modules ./apps/orchestrator/node_modules
 
-# Copy API package.json + prisma schema so Prisma can find the project root
-COPY apps/api/package.json ./apps/api/package.json
-COPY apps/api/prisma ./apps/api/prisma
-RUN pnpm --filter=@mosaic/orchestrator prisma:generate
+# apps/orchestrator/prisma/schema.prisma is a symlink → ../../api/prisma/schema.prisma
+# Docker COPY follows symlinks, so the schema file is already present after
+# "COPY apps/orchestrator ./apps/orchestrator" above.
+# pnpm turbo build runs prisma:generate first (which uses --schema=./prisma/schema.prisma)
+# from within the orchestrator package — no cross-package project-root issues.
 
 # Build the orchestrator app using TurboRepo
 RUN pnpm turbo build --filter=@mosaic/orchestrator

apps/orchestrator/prisma/schema.prisma

@@ -0,0 +1 @@
+../../api/prisma/schema.prisma