Add genlocke creation wizard with backend API and 4-step frontend

Implements the genlocke creation feature end-to-end: Genlocke and
GenlockeLeg models with migration, POST /genlockes endpoint that
creates the genlocke with all legs and auto-starts the first run,
and a 4-step wizard UI (Name, Select Games with preset templates,
Rules, Confirm) at /genlockes/new.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/src/app/schemas/__init__.py

@@ -14,6 +14,7 @@ from app.schemas.encounter import (
     EncounterResponse,
     EncounterUpdate,
 )
+from app.schemas.genlocke import GenlockeCreate, GenlockeResponse, GenlockeLegResponse
 from app.schemas.game import (
     GameCreate,
     GameDetailResponse,
@@ -54,6 +55,9 @@ __all__ = [
     "EncounterResponse",
     "EncounterUpdate",
     "EvolutionResponse",
+    "GenlockeCreate",
+    "GenlockeLegResponse",
+    "GenlockeResponse",
     "GameCreate",
     "GameDetailResponse",
     "GameResponse",