Fix field alignment issue

[mattjohnsonpint]

In Go, a struct's alignment is the maximum of any of its field's alignments. But in AssemblyScript, a class's alignment is always the pointer word size (4 bytes), regardless of its fields.

We had this in the language implementations, but weren't using it correctly in the common langsupport code.

[linear]

HYP-2277 Commerce template giving runtime error `unexpected null pointer for non-nullable type assembly/types/Product`

Copy
{"level":"error","runtime_version":"v0.12.3","execution_id":"crqs40krs90s73dp3h30","build_id":"crqrptps4qk0eok3r7cg","plugin":"hyper-commerce","error":"unexpected null pointer for non-nullable type assembly/types/Product","function":"getCart","duration_ms":0.546594,"time":"2024-09-26T20:20:18.721Z","message":"Error while executing function."}