fix(prisma-next): restore readInstallSql re-export + guard contractSpace (typecheck)

The prior commit removed `readInstallSql` from eql-bundle-v3's re-export, but the
live-test helpers (`test/live/helpers/eql-v3.ts`, `migration-apply-live-pg.test.ts`)
import it from there — a TS2459 the vitest run misses (live suites are skipped)
but the `typecheck` CI step catches. Re-export it. Also non-null-guard
`contractSpace` in the new descriptor-injection test (`contractSpace!`), matching
descriptor.test.ts. typecheck exits 0; 601 tests green.

Claude-Session: https://claude.ai/code/session_01MxTTPaPP16m6br7Hoab94w

Author: coderdan

packages/prisma-next/src/migration/eql-bundle-v3.ts

@@ -32,7 +32,9 @@
  */
 import { readInstallSql, releaseManifest } from '@cipherstash/eql/sql'
 
-export { releaseManifest }
+// Re-exported for the live-test helpers, which read the same install SQL to set
+// up their databases (`test/live/helpers/eql-v3.ts`, `migration-apply-live-pg`).
+export { readInstallSql, releaseManifest }
 
 /**
  * Placeholder the committed v3 baseline op carries in `execute[].sql` in place

packages/prisma-next/test/v3/migration-v3.test.ts

@@ -63,7 +63,7 @@ describe('v3 baseline migration (20260601T0100_install_eql_v3_bundle)', () => {
   it('injects readInstallSql() from @cipherstash/eql into the descriptor at build time', () => {
     // control.ts swaps the placeholder for the install SQL of the pinned
     // @cipherstash/eql, so the applied SQL always matches the resolved version.
-    const v3Baseline = cipherstashDescriptor.contractSpace.migrations[1]!
+    const v3Baseline = cipherstashDescriptor.contractSpace!.migrations[1]!
     const op = (
       v3Baseline.ops as ReadonlyArray<{
         readonly id: string