Entities and Items Cannot Generate New Nether Portals in Unlinked Dimensions

Description:
In Java Edition, when there is no linked Nether portal at the corresponding coordinates in the other dimension, throwing items or sending entities (e.g., mobs, minecarts) through an active Nether portal will trigger the generation of a new portal in the target dimension. However, in Bedrock Edition (since version 1.19.10), entities and items simply remain stuck in the portal without being transported, and no new portal is created. This regression severely impacts cross-dimensional transportation systems.

How to Reproduce:

1. Create a new world and build a Nether portal in the Overworld.

2. Ensure the Nether dimension has never been visited (no pre-existing portals).

3. Throw items or push entities (e.g., cows, pigs, minecarts) into the active Overworld portal.

4. Observe whether they are transported and whether a new portal generates in the Nether.

Observed Result:

• Items and entities remain trapped in the Overworld portal frame.

• No teleportation occurs, and no new Nether portal is generated.

• The global mob cap may be affected due to entities stuck in the portal.

Expected Result:

• Entities and items should pass through the portal and trigger the creation of a new Nether portal at the corresponding coordinates, consistent with Java Edition and pre-1.19.10 Bedrock behavior.

Additional Notes:

• This bug has persisted since Bedrock 1.19.10 and critically disrupts mob transportation systems (e.g., villager breeders, iron farms).

• Urgent restoration of the legacy behavior is requested to align with Java Edition and improve gameplay consistency.