fix(ffi): answer instanceof for TypeScript-derived classes against the derived class

[NathanWalker]

What

On the QuickJS (jsi/ffi) runtime flavor, x instanceof Derived for a @NativeClass-derived class ran the base class's membership check until the derived Objective-C class materialized. A TypeScript-derived constructor inherits the base wrapper's Symbol.hasInstance through the wrapper prototype chain; the closure captures the base native class, so any instance of the base kind tested true (UINavigationControllerImpl instanceof IOSHelper.UILayoutViewController → true).

Impact

@nativescript/core's setViewControllerView gates root-view mounting on exactly that check. For an app whose root view is an imperative Frame (Application.run({ create: () => new Frame() })), the misfire sent core down the layout-controller branch, marshalled the iOSFrame JS helper object into addSubview: (as __NSDictionaryM), and UIKit threw NSInvalidArgumentException: -[__NSDictionaryM superview]: unrecognized selector at boot — a hard crash before first render.

Fix

Symbol.hasInstance is called with the constructor instanceof was invoked on as this (spec: Call(instOfHandler, target, «V»)). In the base wrapper's implementation, detect the inherited invocation (this is neither this constructable nor its proxy and carries __nativeApiTypeScriptState):

• materialized → delegate to the derived wrapper's own hasInstance (correct isKindOfClass: against the derived class)
• not materialized → return false: no instance of an unmaterialized class can exist

After materialization the TS constructor's prototype is already reset to the derived wrapper, whose own hasInstance answers directly, so the new branch only governs the pre-materialization window.

Validation

Reproduced deterministically with a root-Frame NativeScript app on the iOS 26.5 simulator (ios-quickjs build): crash at boot before the fix; app boots, renders, and runs its display-link loop after. A dominative/document-rooted app (no root Frame) was unaffected before and after.

Sibling of #63: that fix marshalled the real Class for the wrapper's own check; this one covers constructors that inherit the check.

🤖 Generated with Claude Code

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