fix: set isExternalSign to true for delegated transactions

[khanti42]

Explanation

EIP-7702 delegated transactions were incorrectly using the user's EOA nonce, causing nonce conflicts and preventing transactions from appearing in the activity tab. In EIP-7702, the delegation address manages its own nonce sequence, not the user's EOA.

This PR sets isExternalSign for EIP-7702 txs.

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Fixes nonce/signing flow for EIP-7702 batches.

• Set isExternalSign = true when adding EIP-7702 batch transactions (presence of nestedTransactions) to bypass internal nonce assignment
• Record delegationAddress for metrics only; do not derive isExternalSign from it
• Update CHANGELOG.md to note the fix

^{Written by Cursor Bugbot for commit 1d3d23a. This will update automatically on new commits. Configure here.}

[matthewwalsh0]

Even if the account is upgraded, it can still sign and submit transactions normally meaning the nonces are valid.

This just records the current delegated address for any transaction, for metrics.

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

[cursor]

EIP-7702 batch isExternalSign override by gas fee token check

Medium Severity

The new isExternalSign = isEIP7702Batch can be overridden by checkGasFeeTokenBeforePublish when a transaction has both nestedTransactions and a gasFeeToken, and the user has sufficient native balance. The checkGasFeeTokenBeforePublish function unconditionally sets isExternalSign = false in this case, which would cause the original nonce conflicts for EIP-7702 batch transactions that the PR aims to fix.