Type intersections using allOf with required keys does not result in required properties

[mithodin]

Describe the bug
I think this a regression of the issue described in #260 (which is closed as resolved). When intersecting two schemas using allOf, where one of the schemas adds a required constraint to a property defined by the other scheme, the constraint is not represented in the generated code.

Minimal reproduction
https://openapi-zod-client.vercel.app/?doc=PYBwpgdghiCWBcACAzAOgAyuQKFhAZsPNoogC6xkA2YSAogB5QC2IN2IUZAFgM7GkA9GTC8yA0ogDmYcSUmkATqJDAIvURIWkATOnRbtpAMZqREOUaMw2sY11hrBAK15rDVyb2PcwzKB6ekgAkyvhIAOQAxIKmrGqQZLyC3r7%2ByQAqAJ7gAEIR2HGqEIn88ql%2BUGUK2eAAgoFkObSIwABGzmDGZPIKIIqgYIoUmr3aAWNGTeBIeCIyipOSbYEK0y1zYAtjtWC5gVBUVADy4UukALTkzUjtnd3nksoAjgCusMoAJqvaV1CPV1CYHCiGisWA8RKFmSFXSgl2dQiQA

Expected behavior
In the given example, I would expect the resulting types to be

const TypeA = z.object({ a: z.number().int(), b: z.number().int() }).partial().passthrough();
const TypeB = TypeA.required({ a: true });

or something to the same effect.