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/useDebouncedValue.ts

@@ -1,5 +1,5 @@
-import { useEffect } from 'react';
-import { useDebouncedState } from './useDebouncedState';
+import { useEffect } from "react";
+import { useDebouncedState } from "./useDebouncedState";
 
 export function useDebouncedValue<T>(value: T, delay = 500) {
   const [state, setState] = useDebouncedState<T>(value, delay);