feat: refactor database connection handling and add legacy map loading functionality

- Updated check-connections.mts to use Prisma with PostgreSQL adapter.
- Introduced databaseUrl.ts for resolving database URLs from environment variables.
- Added legacyMapLoader.ts to load and parse legacy map data.
- Implemented scenarioSeeder.ts to seed scenario data into the database.
- Created tests for scenario seeding in scenarioSeeder.test.ts.
- Configured Prisma datasource in prisma.config.ts to support dynamic database URLs.

packages/infra/prisma.config.ts

@@ -0,0 +1,22 @@
+import 'dotenv/config';
+
+import { defineConfig } from 'prisma/config';
+
+const buildDatabaseUrlFromEnv = (): string => {
+    const host = process.env.POSTGRES_HOST ?? '127.0.0.1';
+    const port = process.env.POSTGRES_PORT ?? '15432';
+    const user = process.env.POSTGRES_USER ?? 'sammo';
+    const password = process.env.POSTGRES_PASSWORD ?? '';
+    const dbName = process.env.POSTGRES_DB ?? 'sammo';
+    return `postgresql://${user}:${password}@${host}:${port}/${dbName}?schema=public`;
+};
+
+const databaseUrl =
+    process.env.DATABASE_URL ?? buildDatabaseUrlFromEnv();
+
+export default defineConfig({
+    schema: 'prisma/schema.prisma',
+    datasource: {
+        url: databaseUrl,
+    },
+});