Divergent development line off origin/main (11a811d): a broad refactor across
routes/services/models/app + a large integration_test expansion (+1000), plus an
untracked game-independent inventory query service and Docker files. Preserved
verbatim before moving the canonical Core checkout to the committed migration
trunk (66c88fb). Reconciling this refactor with the migration trunk is a separate
user decision; nothing here is lost.