Add naming scheme support for genlockes with lineage-aware suggestions

Genlockes can now select a naming scheme at creation time, which is
automatically applied to every leg's run. When catching a pokemon whose
evolution family appeared in a previous leg, the system suggests the
original nickname with a roman numeral suffix (e.g., "Heracles II").

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

backend/src/app/models/genlocke.py

@@ -18,6 +18,7 @@ class Genlocke(Base):
     )  # active, completed, failed
     genlocke_rules: Mapped[dict] = mapped_column(JSONB, default=dict)
     nuzlocke_rules: Mapped[dict] = mapped_column(JSONB, default=dict)
+    naming_scheme: Mapped[str | None] = mapped_column(String(50), nullable=True)
     created_at: Mapped[datetime] = mapped_column(
         DateTime(timezone=True), server_default=func.now()
     )