`new.target` evaluates to `NaN` inside class constructor instead of the constructor reference

[proggeramlug]

Summary

Inside a class constructor, new.target returns the f64 NaN bit pattern instead of the constructor function reference. Surfaced by test-files/test_gap_class_advanced.ts. Reproduces on main (v0.5.503) and HEAD~5 (v0.5.498) — pre-existing.

Minimal repro

class MyConstructable {
  constructor() {
    console.log("new.target:", new.target?.name ?? "undefined");
  }
}
new MyConstructable();

Runtime	Output
node --experimental-strip-types	new.target: MyConstructable
perry	new.target: NaN

Why this matters

new.target is the standard mechanism for:

• Detecting whether a function was called via new vs. as a regular call
• Distinguishing the most-derived constructor in a super() chain (essential for any class-factory or framework that does class.name-based registration)

NaN here is a leaked NaN-boxing tag value — new.target is being lowered to the literal IEEE-754 NaN bit pattern instead of the constructor's class metadata pointer. The fix probably lives near the meta-property lowering site that v0.5.502 touched for import.meta.

[proggeramlug]

Fixed in v0.5.505 (commit 7929011). Two-site HIR fold for new.target.<prop> and new.target?.<prop> matching v0.5.502's import.meta pattern. Limitation deliberately deferred: plain function called WITH new (e.g. new myFunc()) returns the function ref in node but undefined in perry — needs runtime ABI tracking of "called with new" status, out of scope for #449. Class constructor pattern (the dominant shape) is fully fixed.