Fix double-counting resourceFee

[Ryang-21]

• Fixes double counting resourceFee in Transaction.fee due to resourceFee now being handled in TransactionBuilder.build()
• rpc.assembleTransaction() now checks if the raw transaction has already been simulated and subtracts xdr.SorobanTransactionData.resourceFee() if the resulting Transaction.fee remains greater than 0.

[Copilot]

Pull request overview

This PR updates Soroban transaction fee handling in rpc.assembleTransaction() to avoid double-counting resourceFee when re-assembling a transaction that already has Soroban data attached.

Changes:

• Adjust assembleTransaction() fee calculation to subtract any pre-existing Soroban resourceFee before cloning/building the transaction.
• Add unit tests covering re-assembly and pre-existing Soroban data fee scenarios.
• Document the fix in the changelog.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/rpc/transaction.ts	Updates fee handling during transaction assembly to prevent resourceFee being counted twice.
test/unit/transaction.test.ts	Adds tests to ensure fees remain stable across re-assembly and with pre-existing Soroban data.
CHANGELOG.md	Notes the fix and the updated responsibility for applying resourceFee.

Comments suppressed due to low confidence (2)

src/rpc/transaction.ts:94

• The fee-related comment above TransactionBuilder.cloneFrom is now inaccurate: the code no longer adds minResourceFee to fee here, and instead relies on TransactionBuilder.build() to incorporate resourceFee from the Soroban transaction data. Please update/remove this comment so it reflects the current behavior (classic fee may be adjusted by subtracting any pre-existing resourceFee, then passed through as-is).

    // automatically update the tx fee that will be set on the resulting tx to
    // the sum of 'classic' fee provided from incoming tx.fee and minResourceFee
    // provided by simulation.
    //
    // 'classic' tx fees are measured as the product of tx.fee * 'number of
    // operations', In soroban contract tx, there can only be single operation
    // in the tx, so can make simplification of total classic fees for the
    // soroban transaction will be equal to incoming tx.fee + minResourceFee.

CHANGELOG.md:11

• Grammar nit in changelog entry: "as its now" should be "as it's now" (and consider rephrasing to "Removed adding resourceFee in assembleTransaction..." for clarity).

* Removed `resourceFee` adding in `assembleTransaction` as its now handled by `TransactionBuilder.build()`.

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[github-actions]

Size Change: +16.1 kB (+0.04%)

Total Size: 45.1 MB

Filename	Size	Change
dist/stellar-sdk-minimal.js	5.96 MB	+2.71 kB (+0.05%)
dist/stellar-sdk-minimal.min.js	5.07 MB	+1.31 kB (+0.03%)
dist/stellar-sdk-no-axios.js	5.96 MB	+2.71 kB (+0.05%)
dist/stellar-sdk-no-axios.min.js	5.07 MB	+1.31 kB (+0.03%)
dist/stellar-sdk-no-eventsource.js	6.21 MB	+2.71 kB (+0.04%)
dist/stellar-sdk-no-eventsource.min.js	5.28 MB	+1.31 kB (+0.02%)
dist/stellar-sdk.js	6.21 MB	+2.71 kB (+0.04%)
dist/stellar-sdk.min.js	5.28 MB	+1.31 kB (+0.02%)

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