feat(networks): add zk and arbitrum mainnet

[unknownunknown1]

• Added zk and arbitrum to support court cross-chain
• Removed public RPC for Mumbai and ArbSepolia as they were replaced by private ones

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PR-Codex overview

The focus of this PR is to update the fallback Web3 URLs for various networks and remove redundant URLs.

Detailed summary

• Updated XDAI and ZKSync fallback URLs
• Removed redundant Mumbai and Arbitrum URLs

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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud