Unify transaction error handling and receipt checks

[cyc60]

Description

All tx_manager.transact() call sites hand-rolled the same wrapper: try/except ContractCustomError with decode_custom_error, a generic except Exception with format_error, and an if tx_receipt is None check — with inconsistent log levels, inconsistent verbose dumps, and two sites with partial or no handling.

This adds a shared transact_checked() helper in src/common/transaction.py that normalizes reverts, RPC errors, and unconfirmed receipts into a logged None, and converts all 9 call sites to use it:

• Failure logging is now uniform: logger.error plus a settings.verbose exception dump everywhere (consolidate/withdrawals previously logged failures at info level).
• submit_harvest_transaction gains generic-exception handling it previously lacked.
• MulticallContract now includes ErrorMixin, so tx_aggregate reverts are decoded and logged instead of propagating undecoded.
• The reward splitter raises RuntimeError on a revert instead of re-raising ContractCustomError; the loop aborts either way.
• The raising flows (reward splitter, meta vault deposit/state update) keep their raise-on-failure semantics; the hash-returning flows keep returning HexStr | None.