Transaction Operation Effect Aggregator

[Kingsman-99]

Description

After a transaction is submitted, its effects (balance changes, offer fills, trust line creations) are scattered across multiple Horizon /effects pages. The SDK surfaces raw operation records but does not aggregate the net effect across all operations in a transaction, making it difficult for callers to show a simple "what changed" summary. An effect aggregator should consolidate all effects into a per-account balance delta summary.

Technical Context

Add src/effectAggregator.ts. Uses @stellar/stellar-sdk Server.operations() with includeFailed: false and .effects() sub-resource to fetch effects per operation. Produces AccountEffectSummary[] in src/types.ts. Integrates with src/receipt.ts to attach the effect summary to PaymentReceipt. Uses src/horizonPaginator.ts to walk all effect pages.

Acceptance Criteria

• aggregateEffects(txHash: string): Promise<AccountEffectSummary[]> returns one summary per affected account with { accountId, assetDeltas: { asset, delta }[] }
• Correctly handles multi-operation transactions by summing deltas across all operations for the same account and asset
• Filters out intermediate DEX effects (intermediate offer fills) and reports only the net asset change per account
• Attaches effectSummary to PaymentReceipt in src/receipt.ts when includeEffects: true is set in config
• Unit tests use mock effect page sequences and assert correct aggregation for a two-recipient payment with path conversion
• All CI checks (npm test, npm run build, ESLint/TypeScript) pass and the branch has no merge conflicts

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[probablyABug]

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hi, i would like to work on this.

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[ololadedavidvictor-bit]

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hello please can i work on this issue

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[Zalgia-Saga]

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I will like to work on this.

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