chore: gitignore tsc -b build cache + vite.config emit

Build pipeline 'tsc -b && vite build' produces .tsbuildinfo + an
accidental vite.config.{js,d.ts} emit from project references.
Untrack + ignore so they don't keep coming back to dirty git status.

.gitignore

@@ -5,3 +5,9 @@ dist
 *.local
 .DS_Store
 *.swp
+
+# TypeScript build cache + accidental emit from vite.config (tsc -b)
+*.tsbuildinfo
+vite.config.d.ts
+vite.config.js
+vite.config.js.map