fix: wait for confirmed gasless transactions

[cesarenaldi]

Summary

• wait for gasless relayer transactions to reach STATE_CONFIRMED before resolving transaction handles
• update async and sync relayer workflow tests to model confirmed transaction outcomes
• cover the mined-to-confirmed polling transition directly

Why

The relayer can mine a Deposit Wallet transaction before the wallet registry is ready. Returning from wait() at STATE_MINED lets follow-up Deposit Wallet calls race the registry and fail with wallet is not registered.

Verification

• uv run pytest tests/unit/test_relayer_submit_poll.py tests/unit/test_relayer_approve_erc20.py tests/unit/test_sync_relayer_workflows.py tests/unit/test_relayer_setup_trading_approvals.py tests/unit/test_place_order_recovery.py
• uv run ruff check .
• uv run ruff format --check .
• uv run pyright
• uv run pytest -m "not integration"

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Note

Medium Risk
Changes when gasless transaction handles resolve, which affects deposit-wallet relayer workflows; behavior is narrower (longer waits) but reduces race failures on follow-up calls.

Overview
Gasless relayer wait() / poll_until_terminal now treat only STATE_CONFIRMED as success, not STATE_MINED, so callers keep polling through the mined step until the deposit wallet registry is ready.

_TERMINAL_SUCCESS in poll.py drops MINED; async/sync handles and flows that depend on terminal polling (approvals, setup, place-order recovery) inherit the stricter gate. Unit tests mock STATE_CONFIRMED outcomes and add coverage that a first poll returning STATE_MINED requires a second poll before returning an outcome.

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