feat: add initial project configuration and smoke tests

- Created pnpm workspace configuration to manage packages.
- Added a placeholder .gitkeep file in the scripts directory.
- Implemented a smoke test script to validate core API and web endpoints.
- Established TypeScript base configuration for consistent compilation settings.
- Introduced Turbo configuration for task management and build processes.

packages/api/prisma/schema.prisma

@@ -0,0 +1,14 @@
+datasource db {
+  provider = "postgresql"
+}
+
+generator client {
+  provider     = "prisma-client"
+  output       = "../src/generated/prisma"
+  moduleFormat = "cjs"
+}
+
+// Placeholder model — removed when real models are added in feature plans
+model Placeholder {
+  id String @id @default(uuid())
+}