Run oxfmt across repo, add format script and ignore config

Format all non-generated files with oxfmt via `vp fmt`. Add
.oxfmtignore to skip bindings/ and wasm-pack output. Add npm
format script and update DEVELOPMENT.md docs.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src-web/hooks/useKeyboardEvent.ts

@@ -1,8 +1,8 @@
-import { useEffect } from 'react';
+import { useEffect } from "react";
 
 export function useKeyboardEvent(
-  event: 'keyup' | 'keydown',
-  key: KeyboardEvent['key'],
+  event: "keyup" | "keydown",
+  key: KeyboardEvent["key"],
   cb: () => void,
 ) {
   // oxlint-disable-next-line react-hooks/exhaustive-deps -- Don't have `cb` as a dep for caller convenience