Transaction confirmation and lifecycle tracking

Start by reading celestia-app's pkg/user/tx_client.go, especially ConfirmTx() and its eviction handling, then inspect the CometBFT TxStatus endpoint. Implement the specified TxTracker lifecycle, including polling, resubmission, structured failures, and pending hashes. Done means confirmation, rejection, eviction, and timeout behavior are represented by TxResult and Pending().

Summary

Implement transaction lifecycle tracking from broadcast through confirmation or rejection.

Parent: #4

Flow

Broadcast (SYNC) → Mempool → Included in Block → Committed
                      │              │
                      ▼              ▼
                   Evicted        Rejected (execution error)

Requirements

Broadcast

• Use BroadcastTxSync (returns after mempool acceptance, not block inclusion)
• Capture tx hash from response
• Handle immediate rejection (invalid tx, mempool full)

Confirmation polling

• Poll TxStatus at configurable interval (default: 1s)
• Timeout after configurable duration (default: 2 minutes)
• Return confirmed height and gas used on success

Eviction handling

• If tx is evicted from mempool, optionally resubmit with same or bumped gas price
• Max resubmission attempts: configurable (default: 1)
• Log eviction events for debugging

Rejection handling

• If tx is included but execution fails, capture error code, codespace, gas wanted/used
• Reset nonce to enable subsequent transactions (#8)
• Return structured error with all context

Timeout handling

• If confirmation times out, return error but do NOT assume tx failed (it may still confirm)
• Track "unconfirmed" transactions for later reconciliation

Interface

type TxResult struct {
    TxHash   string
    Height   int64
    GasUsed  int64
    Code     uint32       // 0 = success
    Error    string       // non-empty if Code != 0
    Duration time.Duration // broadcast to confirmation
}

type TxTracker interface {
    Submit(ctx context.Context, txBytes []byte) (*TxResult, error)
    Pending() []string // tx hashes still awaiting confirmation
}

References

• celestia-app pkg/user/tx_client.go — ConfirmTx(), eviction handling
• CometBFT TxStatus endpoint