Trace failed transactions

[fbac]

Trace failed blockchain transactions and return revert output in pkg/blockchain/client.ExecuteTransaction with a fixed gas limit of 5,000,000 and a 20s wait timeout

• Add sentinel errors ErrTxFailed, ErrTxFailedNoError, ErrTxNotFound, and ErrTxGenesisNotTraceable in client.go
• Modify pkg/blockchain/client.ExecuteTransaction to remove gas estimation and NoSend flow, set GasLimit to 5,000,000, extend wait timeout to 20s, and on mined failure trace via debug_traceTransaction to return revert output as a BlockchainError in client.go
• Update pkg/blockchain/client.WaitForTransaction to return ErrTxFailed on failed receipts, treat ethereum.NotFound as a wait condition, and adjust polling behavior in client.go
• Add traceTransactionOutput helper to poll debug_traceTransaction with callTracer and return the output field in client.go
• Change BlockchainError.Error to return only the high-level message in errors.go
• Update tests to assert human-readable custom error names instead of hex selectors in app_chain_admin_test.go, node_registry_admin_test.go, and settlement_chain_admin_test.go

📍Where to Start

Start with the transaction flow in ExecuteTransaction in client.go, then review WaitForTransaction and traceTransactionOutput in the same file.

Changes since #1211 opened

• Standardized error handling across blockchain admin components by replacing string-based error detection with IsNoChange() method calls [c5a26ff]
• Refactored control flow in blockchain client transaction handling functions by replacing switch statements with explicit conditional checks [c5a26ff]
• Updated test expectations to align with standardized no-change error handling [c5a26ff]

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Macroscope summarized c5a26ff.

[graphite-app]

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