chore: ignore and remove .ui-review artifacts

Drop tracked UI review/acceptance screenshot dirs and ignore
.ui-review/ and .ui-review-*/ so they stay local-only.

.gitignore

@@ -27,3 +27,7 @@ logs/
 .*.pid
 apps/server/bin/
 *.tsbuildinfo
+
+# UI review / acceptance screenshots (local only)
+.ui-review/
+.ui-review-*/