parametrize node id type

[crclark]

To allow for graphs bigger than max value of u32

[crclark]

We would need to work around lumol-org/soa-derive#35, so I will delay this work for now.

[crclark]

It actually makes more sense to shard the data structure rather than allow for huge graphs, because using bigger node id types has a significant impact on memory usage -- the data structure internally is mostly storing many elements of the type of the node id, so doubling its size has a massive impact on memory usage. Real-world usage would want to shard well before the billions-scale that a 32 bit id allows, anyway.