Wasm in demo page is unoptimized

[kripken]

Running wasm-opt -O on it, it becomes less than half the size, 723,715 bytes instead of 1,576,113.

This may not just affect size, as wasm-opt --metrics -O --metrics reports this in the diff:

 [vars]         : 10448     -79887

which means the number of local variables goes from 90335 to 10448, almost 9x less. Wasm VMs may not be able to run unoptimized code with excessively many locals at full speed (they may end up stuck in baseline tiers).

(Aside from the Binaryen optimizer, LLVM opts should also be run, but I can't tell if they were or not from the binary.)