Boat Standing Fix

Port to Minecraft 26.2. Verified via decompiling the actual 26.1 and 26.2 merged server jars that both mixin targets are byte-identical and AbstractBoat stays in the same package, so no source changes were needed, only the target Minecraft version. Also includes the self-match fix from the 26.1.x 1.0.1 release: the boat-proximity check now excludes the query subject itself, so a boat's own vehicle-movement validation is no longer unconditionally disabled.