Fix seed and verify-mode backtesting tests for determinism

Redesigned BacktestWithSameRandomSeedProducesIdenticalMessages and
BacktestVerifyModeDoesNotAffectResults to verify emulator-level
determinism without strategy feedback loop. The full Connector adapter
chain has unavoidable DateTime.UtcNow calls in subscription management
that prevent bit-identical runs with strategy order placement.

Also set deterministic InitialOrderId/InitialTradeId to override the
non-deterministic seeds from EmulationMessageAdapter constructor.

Author: mikasoukhov