using/await using rejects bound functions and proxied callables as dispose methods

### Version v24.18.0 ### Platform ```text Microsoft Windows NT 10.0.26200.0 x64 (also reproduced on Linux x64 per downstream reports) ``` ### Subsystem V8 / explicit resource management ### What steps will reproduce the bug? ```js const fn = async function () { console.log('disposed'); }; // 1. bound function as async dispose method: throws try { await using a = { [Symbol.asyncDispose]: fn.bind(null) }; } catch (e) { console.log('bound async:', e.message); } // 2. bound function as sync dispose method: throws try { using b = { [Symbol.dispose]: (function () {}).bind(null) }; } catch (e) { console.log('bound sync :', e.message); } // 3. proxy-wrapped callable as dispose method: throws try { await using c = { [Symbol.asyncDispose]: new Proxy(fn, {}) }; } catch (e) { console.log('proxied fn :', e.message); } // 4. ordinary function: works await using d = { [Symbol.asyncDispose]: fn }; console.log('plain fn accepted'); ``` Output: ```text bound async: Symbol(Symbol.asyncDispose) is not a function bound sync : Symbol(Symbol.dispose) is not a function proxied fn : Symbol(Symbol.asyncDispose) is not a function plain fn accepted disposed ``` ### What is the expected behavior? Why is that the expected behavior? All four cases should dispose. Per the Explicit Resource Management proposal, the dispose method is retrieved with GetMethod, which throws only when the value is neither undefined nor callable. Bound function exotic objects and proxies over callables are both callable (`typeof` reports `"function"` and they invoke fine), so rejecting them deviates from the spec. It looks like the implementation checks for a specific function instance type rather than IsCallable. ### What do you see instead? `TypeError: Symbol(Symbol.asyncDispose) is not a function` (respectively `Symbol.dispose`) at the `using` declaration site, for values that are callable. ### Additional information Found while debugging unjs/jiti#437: jiti's `interopDefault` proxy returns bound methods, so an…