chore(db): add drizzle migration pipeline with empty schema

documentation/roadmap.md

@@ -15,8 +15,8 @@ Each phase produces a working, deployable increment. Nothing is built speculativ
 - [x] Set up Vitest in `api` and `web` and both packages
 - [x] Scaffold Express app with `GET /api/health`
 - [x] Scaffold Vite + React app with TanStack Router (single root route)
-- [ ] Configure Drizzle ORM + connection to local PostgreSQL
-- [ ] Write first migration (empty — just validates the pipeline works)
+- [x] Configure Drizzle ORM + connection to local PostgreSQL
+- [x] Write first migration (empty — just validates the pipeline works)
 - [ ] `docker-compose.yml` for local dev: `api`, `web`, `postgres`, `valkey`
 - [ ] `.env.example` files for `apps/api` and `apps/web`
 - [ ] update decisions.md

packages/db/drizzle.config.ts

@@ -9,7 +9,7 @@ config({
 
 export default defineConfig({
   out: "./drizzle",
-  schema: "./src/schema.ts",
+  schema: "./src/db/schema.ts",
   dialect: "postgresql",
   dbCredentials: { url: process.env["DATABASE_URL"]! },
 });

packages/db/drizzle/meta/_journal.json

@@ -0,0 +1 @@
+{"version":"7","dialect":"postgresql","entries":[]}