Non-Siege Battle rules update

> 310.8. If a non-Siege battle’s defense is 0, it’s put into its owner’s graveyard. (This is a state-based action. See rule 704.)
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> 704.5w If a non-Siege battle has defense 0, it’s put into its owner’s graveyard.
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> 704.5x If a battle has no player in the game designated as its protector and no attacking creatures are currently attacking that battle, that battle’s controller chooses an appropriate player to be its protector based on its battle type. **If the battle has no battle type, its controller must be chosen.** If no player can be chosen this way, the battle is put into its owner’s graveyard. See rule 310, “Battles.”

No files or tests are named. Start by locating the battle state-based-action and rules handling for rules 310 and 704.5. Verify zero-defense non-Siege battles and battles without a battle type follow the listed graveyard and protector-selection outcomes.

Written by the indexing model from the issue text.