fix(scripts): resolve tsconfig errors in check-pr-title workflow (#1332)

Set rootDir to "." to fix TS5011 (common source directory conflict when
including both scripts/ and demo/) and set target to ES2019 to fix TS5107
(ts-node's default ES5 target is deprecated in TypeScript 7.0).

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: sserrata

tsconfig.json

@@ -1,5 +1,7 @@
 {
   "compilerOptions": {
+    "rootDir": ".",
+    "target": "ES2019",
     "resolveJsonModule": true,
     "esModuleInterop": true,
     "noEmit": true,