fix ec.error shape in web platform

[kiftio]

What changes are you making?

• Update web ec.error handling to match the Swift/Android protocol shape: params.error.
• Add explicit EcErrorParams typing for the raw JSON-RPC params envelope.
• Reject the old invalid ec.error shape where ucp and messages are directly under params.
• Update tests to send valid ec.error params via makeErrorParams() and keep a regression test for the old shape.

How to test

• pnpm --dir platforms/web run format:check
• pnpm --dir platforms/web run typecheck
• shadowenv exec --dir /Users/danielkift/ck -- /opt/dev/bin/dev web test
• git diff --check

Before you merge

Important

• I've added tests to support my implementation
• I have read and agree with the Contribution Guidelines
• I have read and agree with the Code of Conduct
• I've updated the relevant platform README (platforms/swift/README.md and/or platforms/android/README.md)

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Releasing a new Swift version?

• I have bumped the version in ShopifyCheckoutKit.podspec
• I have bumped the version in platforms/swift/Sources/ShopifyCheckoutKit/ShopifyCheckoutKit.swift
• I have updated platforms/swift/CHANGELOG.md
• I have updated the SwiftPM/CocoaPods version snippets in platforms/swift/README.md (major version only)

Releasing a new Android version?

• I have bumped the versionName in platforms/android/lib/build.gradle
• I have updated platforms/android/CHANGELOG.md
• I have updated the Gradle/Maven version snippets in platforms/android/README.md

Tip

See the Contributing documentation for the full release process per platform.

[github-actions]

Web — Coverage Report

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