feat: Solaxy Chain support

[Marcolist]

Summary & Motivation

This PR adds support for the Solaxy (SVM) mainnet to the Phantom Wallet SDK.

• Introduces a new NetworkId.SOLAXY_MAINNET (solaxy:1936682104)
• Adds corresponding configuration to NETWORK_CONFIGS
• Includes CAIP-2 mapping, explorer URLs, and chain metadata
• No RPC endpoint added — Phantom manages its own RPCs internally
• Aligns with existing Solana-based network definitions for SVM compatibility

This addition enables developers to identify and interact with Solaxy accounts and explorers
through the standard SDK interfaces.

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Did you add a changeset?

Yes

Run locally:

yarn changeset

[Marcolist]

Thanks for reviewing!
Solaxy is an SVM-based L2 compatible with Solana programs.
The provided metadata follows existing Solana mainnet conventions.
Looking forward to feedback and integration testing.