T3 Wave 4 (T27). Lobby now supports stacking multiple modifier
profiles for solo play. The primary picker stays single-select for
backwards compatibility with multiplayer create/join (which sends
exactly one ModifierProfile on the wire today); a 'Stacked (solo
only)' list below it lets the user append additional profiles, with
up/down reorder and remove buttons per entry.
State:
- additionalProfiles: ModifierProfile[] holds the stack-on-top
entries. Empty by default; appears in the UI only when the primary
picker has a selection.
resetToFreshGame branches:
- 0 or 1 profile total → unchanged single-profile fast path through
EngineOptions.profile (preserves T1/T2 behaviour exactly).
- 2+ profiles → constructs a profile-less engine, then runs
applyProfilesToSession across the full ordered stack so additive
contributions compose correctly across profiles. Sets activeProfile
to the LAST entry as a UI-display canonical (header badge etc.).
UI:
- Primary picker unchanged.
- profile-stack list with data-testids profile-stack, profile-stack-{i},
profile-stack-{i}-up/down/remove for e2e access.
- profile-stack-add dropdown filters out already-selected ids.
Multiplayer wire shape unchanged — sending the stack to the server is
a future T27 extension that would touch the protocol.
E2E for the new stacking UI defers to T29; existing 9/9 solo-smoke
+ all 1378 unit tests pass.
Joey Yakimowich-Payne
31af101b55