feat(network): add automated transaction resubmission with gas escalation (#661)

[nekwasar]

Closes #661

Changes

src/network/nonce_tracker.py

• PendingSubmission dataclass — tracks a single pending transaction with tx_id, base_fee, submitted_at timestamp, and attempts counter
• TransactionResubmitter class — automated resubmission manager with multiplicative fee escalation:
  • track(tx_id, base_fee) — register a transaction for escalation monitoring
  • untrack(tx_id) — remove a completed transaction from monitoring
  • set_resubmit_fn(fn) — set/replace the resubmission callback
  • escalate_pending() — check all pending txs and escalate those past the timeout
  • get_pending_count() / get_pending_ids() — inspection helpers
  • _compute_escalated_fee(sub) — applies min(current_fee * factor, max_fee)
• Configurable: initial_fee (default 100), escalation_factor (default 1.5x), max_fee (default 10,000), resubmit_timeout (default 30s)
• All constructor params validated (initial_fee < 100, factor <= 1.0, max_fee < initial_fee, timeout <= 0 raise ValueError)
• Thread-safe via threading.Lock on _pending dict

tests/test_nonce_tracker.py

• 11 tests for gas escalation resubmission:
  • Construction defaults and custom params
  • Invalid param rejection (4 edge cases)
  • Track/untrack lifecycle
  • Duplicate tracking prevention
  • Fee computation (including cap at max_fee)
  • No escalation when timeout not reached
  • Callback invoked with correct escalated fee
  • Multiple pending txs escalated correctly
  • Callback failure does not crash or block others
  • set_resubmit_fn works after construction

Acceptance Criteria

• Unconfirmed transactions automatically resubmitted with escalated inclusion fees after timeout limits
• pytest tests/test_nonce_tracker.py -k test_gas_escalation_resubmission passes

Type of Change

• New feature (non-breaking)

ends #661

[drips-wave]

@nekwasar Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

Learn more about application limits