fix(web): decode Postgres blob data as hex bytes

[pengqima]

Checklist

• My change requires a documentation update, and I have done it.
• I have added tests to cover my changes.
• I have filled out the description and linked the related issues.

Description

Fix the blob data proxy response for Postgres-backed storage references.

The Postgres blob data endpoint returns a JSON string containing 0x-prefixed hexadecimal data. The proxy previously passed the hexadecimal characters to Buffer.from() without specifying an encoding, causing them to be interpreted as UTF-8 text instead of the original binary bytes.

This change decodes the value using the hex encoding, matching the existing handling for text-based storage responses.

Motivation and Context (Optional)

For example, 0x0001feff was previously returned as the bytes representing the ASCII string 0001feff (3030303166656666) instead of the expected binary bytes (0001feff).

A regression test now verifies that Postgres-backed responses preserve the original blob bytes.

Related Issue (Optional)

Screenshots (if appropriate):

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🦋 Changeset detected

Latest commit: 29bff68

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@blobscan/web	Patch

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