Extract the FlatBuffers builders for the wire tables shared by the backend push
encoder and the gateway edge transcoder — GameView, MoveRecord, StateView,
AccountRef, Invitation and their nested rows — into a new scrabble/pkg/wire
package. Both callers keep their local builder signatures (no call sites move)
but now map their own source types (the backend's notify.* payloads and the
decoded engine.MoveRecord; the gateway's backendclient.* REST DTOs) to neutral
wire.* structs and delegate the construction to package wire, the single
definition of the nested-table layout.
Behaviour-preserving: the verified-identical field sets mean the wire bytes
decode the same, and the notify + transcode round-trip tests pass unchanged. The
fiddly Start/Add/End + reverse-prepend vector boilerplate now lives once; the two
encode files shrink while pkg/wire carries the shared logic.
Ilia Denisov
b47c47e969