Log event only when stored

[fbac]

Log PayerReportSubmitted events only on successful storage in pkg/indexer/settlement_chain/contracts/PayerReportManagerStorer.StoreLog

The handler for PayerReportSubmitted events in pkg/indexer/settlement_chain/contracts/payer_report_manager_storer.go now logs success only when storage succeeds and treats zero-row inserts as an existing report condition. The IPayerReportStore.StoreReport signature changes to return the number of affected rows and an error, and Store.StoreReport returns (int64, error) from the underlying insert operation.

• Update PayerReportManagerStorer.StoreLog to conditionally log success on nil error and suppress errors tagged with ErrReportAlreadyExists in payer_report_manager_storer.go
• Add ErrReportAlreadyExists and adjust PayerReportManagerStorer.setReportSubmitted to use (numRows, error) from store.StoreReport, returning a non-recoverable error when numRows == 0, and calling SetReportSubmitted only on new inserts in payer_report_manager_storer.go
• Change IPayerReportStore.StoreReport to return (int64, error) in interface.go
• Modify Store.StoreReport to return (int64, error) and propagate affected row count in store.go

📍Where to Start

Start with the PayerReportManagerStorer.StoreLog handler in payer_report_manager_storer.go, then review PayerReportManagerStorer.setReportSubmitted to see how (numRows, error) is used and how ErrReportAlreadyExists is handled.

Changes since #1217 opened

• Modified IPayerReportStore.StoreReport method signature to return (int64, error) instead of just error [9ea929f]
• Updated all StoreReport method calls in tests to capture and assert the new int64 return value [9ea929f]
• Modified execution order in contracts.PayerReportManagerStorer.setReportSubmitted method to call store operation before error handling [33c55df]

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Macroscope summarized 33c55df.

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