chore: re-enroll somniatestnet

[paulbalaji]

Summary

• Re-enabled somniatestnet and re-enrolled its default ISM across testnet chains
• Updated addresses for somniatestnet enrollment on all testnet chains

Test plan

• Verify somniatestnet metadata is correct
• Verify updated addresses are valid

🤖 Generated with Claude Code

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Note

Medium Risk
Registry-only config changes, but they alter security module addresses across many testnets; incorrect addresses could break message verification/routing for those environments.

Overview
Re-enables somniatestnet by removing its disabled availability marker from chains/somniatestnet/metadata.yaml, and publishes the change as a minor bump via a new changeset.

Updates the interchainSecurityModule address in several testnet addresses.yaml files (e.g., sepolia, arbitrumsepolia, basesepolia, optimismsepolia, polygonamoy, fuji, bsctestnet, celosepolia, cotitestnet, modetestnet, hyperliquidevmtestnet, incentivtestnet, and somniatestnet) to point to the re-enrolled/default ISM.

^{Written by Cursor Bugbot for commit 8b19236. This will update automatically on new commits. Configure here.}