feat(Networks): add zk Sepolia

[unknownunknown1]

PR-Codex overview

This PR updates web3 fallback URLs, adds a new subgraph link, and includes a new environment variable for ZKSync Sepolia.

Detailed summary

• Updated web3 fallback URLs for different networks
• Added a new subgraph link for Kleros Display Sepolia
• Included a new environment variable for ZKSync Sepolia

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[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues

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

See analysis details on SonarCloud

[sonarqubecloud[bot]]

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