docs: update outdated arc.network domain references to arc.io

[mrnetwork0001]

Hi team! I noticed that Arc has migrated its domain to arc.io, but there were still 38 references to the old arc.network domain across the documentation and README. I've gone ahead and updated all of them to point to the correct new domain.

[nenadmilosevic95]

Service endpoint domains haven't migrated.

Thanks for the contribution! The www.arc.io and docs.arc.io changes look correct and good to merge.

However, the service endpoint subdomains introduced by this PR don't resolve yet:

https://rpc.quicknode.testnet.arc.io/   → DNS FAIL (host not found)
https://rpc.drpc.testnet.arc.io/        → DNS FAIL (host not found)
https://rpc.blockdaemon.testnet.arc.io/ → DNS FAIL (host not found)
https://snapshots.arc.io/               → DNS FAIL (host not found)

The corresponding arc.network endpoints are still live. We'd suggest reverting the service endpoint changes and keeping only the www/docs updates in this PR.

[mrnetwork0001]

Service endpoint domains haven't migrated.

Thanks for the contribution! The www.arc.io and docs.arc.io changes look correct and good to merge.

However, the service endpoint subdomains introduced by this PR don't resolve yet:

https://rpc.quicknode.testnet.arc.io/   → DNS FAIL (host not found)
https://rpc.drpc.testnet.arc.io/        → DNS FAIL (host not found)
https://rpc.blockdaemon.testnet.arc.io/ → DNS FAIL (host not found)
https://snapshots.arc.io/               → DNS FAIL (host not found)

The corresponding arc.network endpoints are still live. We'd suggest reverting the service endpoint changes and keeping only the www/docs updates in this PR.

Thanks for the feedback!
I have reverted all the service endpoint subdomains (RPCs and snapshots) back to arc.network since they do not resolve yet, while keeping the main website and documentation links updated to arc.io. The PR has been updated with these changes.

[osr21]

Hey — heads up, this PR appears to be going in the wrong direction. It replaces working arc.network URLs with the older arc.io domain, but arc.io / docs.arc.io is the dead/redirect domain. The live official docs are at docs.arc.network and the website is arc.network.

Specifically:

• https://www.arc.network/ → ✅ live (being replaced with arc.io ❌)
• https://docs.arc.network/arc/tutorials/deploy-on-arc → ✅ live (being replaced with docs.arc.io ❌)

There's actually an open PR (#77) fixing grammar/typos in the same files — worth checking there isn't a conflict.

(Note: I ran into this while building a CCTP V2 bridge dapp on Arc testnet and discovered docs.arc.io returns 404s.)