feat(14-05): create SQLite-to-Postgres data migration script

- One-time migration script with type conversions (unix timestamps to Date, int to bool)
- Migrates all 13 tables in FK dependency order
- Resets serial sequences after data migration
- Adds db:migrate-from-sqlite npm script

package.json

@@ -13,7 +13,8 @@
 		"test": "bun test tests/",
 		"test:e2e": "bunx playwright test",
 		"test:e2e:ui": "bunx playwright test --ui",
-		"lint": "bunx @biomejs/biome check ."
+		"lint": "bunx @biomejs/biome check .",
+		"db:migrate-from-sqlite": "bun run scripts/migrate-sqlite-to-postgres.ts"
 	},
 	"devDependencies": {
 		"@biomejs/biome": "^2.4.7",