Java 26.3 data: serverbound packet table correction

Built from the tested support/java-26.3 wrapper (9a04c48) and its pinned data submodule (minecraft-data 6753283). Maps serverbound play 0x3f to spectator_action as in the vanilla 26.3 server and removes the nonexistent arm_animation and spectate_entity packets.

SHA-256: 53f0f0325ed972cdc5e6ed76c3d4254dc358eec6ec1693bcb7fbc02333501db9
npm integrity: sha512-+rDvXi+uRb5gDM6XfoWT7XCowuwcUT+aXCw9STsKmu/BP3ICWqlgiq3t0sVAuI6K6AHnGOy3sNLs8mzI/x8JjQ==