File the last METATYPE deferred enhancement: List(T).append at comptime
bails ('struct_get: base has no fields') in a type-construction ::.
Standalone repro + two-layer root cause (null comptime allocator at
scanDecls; *T slot_ptr struct_get) + investigation prompt. Non-blocking:
array-literal locals already build variant lists (examples/0620/0624).
Checkpoint + Known issues reference 0141.
0f88525884