[WIP] Deprecate rpc, firehose, substreams for blast-sepolia

[Copilot]

Deprecate blast-sepolia

Following the quick deprecation mode from RELEASING.md:

• Update blast-sepolia meta.ts to set deprecated_at for rpc, firehose, and substreams
• Run bun run update to regenerate data and types
• Run bun run release to create changeset and version bump
• Verify all changes are correct

Original prompt

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This section details on the original issue you should resolve

<issue_title>Deprecate blast-sepolia</issue_title>
<issue_description>Deprecate rpc, firehose, substreams for blast-sepolia. Follow https://github.com/pinax-network/chains/blob/main/RELEASING.md#quick-mode-to-quickly-deprecate-a-chain</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Deprecate blast-sepolia #52

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[changeset-bot]

⚠️ No Changeset found

Latest commit: e50e7e3

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