chore(frontend): let lint-staged pass commits that stage only generated files

lint-staged hands every staged src/**/*.ts file to oxfmt and oxlint, but
both ignore src/generated, so a commit whose only TypeScript change is a
regenerated schema (a validator tag edit plus make gen) aborts with
"Expected at least one target file". Tell both tools an empty selection
is not an error.

frontend/package.json

@@ -29,8 +29,8 @@
   },
   "lint-staged": {
     "src/**/*.{ts,tsx}": [
-      "oxfmt",
-      "oxlint --fix"
+      "oxfmt --no-error-on-unmatched-pattern",
+      "oxlint --fix --no-error-on-unmatched-pattern"
     ]
   },
   "dependencies": {