feat: add Prisma schema (MySQL) and Docker Compose for db/redis

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

prisma.config.ts

@@ -0,0 +1,10 @@
+import path from "node:path";
+import "dotenv/config";
+import { defineConfig, env } from "@prisma/config";
+
+export default defineConfig({
+  schema: path.join("prisma", "schema.prisma"),
+  datasource: {
+    url: env("DATABASE_URL"),
+  },
+});