Rework of end platform and end portal structures

Sorry to say this, but right now end frames and end platform look like a stopgap solution that wasn't finished.

First of all - end frames float in the air in dungeons. Was this intended, or is it an off-by-one error? What we have now doesn't really look very good (personal but not uncommon opinion).

And second - spawning in the end is... anticlimactic. You just randomly spawn on this plain obsidian square floating in the air. Looks and feels like it was prototyped and forgotten.

The most irking thing is usage of bedrock in the end gates, towers and portal back home. I find bedrock that bedrock should stay an exclusive, special kind of block, functioning only as an invisible wall that stops players from falling off the map. The idea of something indestructible near the dimension's spawn feels wrong and not along Minecraft's style.

I propose, that in The End dimension a same-shape portal frame/ring was created that just simply stays inactive until the dragon is defeated. Instead of a square platform and fountain-portal, there would be just one, consistent structure.