Fix Ice Rod overworld ice tiles transition

[scawful]

Currently, when the player uses the Ice Rod in an area where the water leads to a transition without the flippers they get stuck in a drown and refresh loop.

Potential solutions:

• Block off access to transitions before the flippers are obtained.
• Make drowning hurt the player, leading to a death loop on transition.
• Prevent the Ice Rod from creating a walkable ice tile at the edges of an overworld map.
• Remove the Ice Rod walking ability entirely.

[scawful]

The Ice Rod ability is being deprioritized for water traversal in favor of Deku Link hovering via Deku Flower, so the transitions are not as large of a concern ATM.