Subnet id should be reflected in the URL

[arikan]

So that we can view the subnet directly. It should be like:

https://explorer.avax.network/subnets/:id https://explorer.avax.network/subnets/:id#blockchains https://explorer.avax.network/subnets/:id#validators https://explorer.avax.network/subnets/:id#pending-validators https://explorer.avax.network/subnets/:id#keys

[strictlymomo]

Hi there, sorry for the delayed response.

I'm currently working on redesigning the path structures. Subnets and blockchains will be top-level and their child entities will be nested within.

This issue will be reflected in the changes.