Minecart carrying a boat with riding villager becomes perpetual‑motion, moves forever without input

**Short description of the issue**
When a mob (such as a villager) rides inside a boat, and that boat becomes a passenger of a minecart, the minecart obtains perpetual self‑propulsion and moves forever on rails. This affects most rideable mobs, not just villagers. Players do not trigger this bug.

**Steps to reproduce the issue**
1. Create a brand‑new creative single‑player world.
2. Spawn a villager and let the villager enter a boat.
3. Force the boat (with villager inside) to become a passenger of a minecart.
4. Observe the minecart on normal rails.

**Expected result**
The minecart should stay still or slow to a stop by friction. It should only move when pushed by players, mobs or powered rails.

**Actual result**
The minecart moves continuously on its own without any input. It never slows down from friction. On corners or blocked positions it vibrates/jitters heavily.
The perpetual motion only stops if:
‑ the mob inside the boat is killed
‑ the boat is destroyed
‑ the minecart is destroyed
Reloading the world does not resolve the bug.