Support for Python 3.14 on Windows

[cjdsellers]

NautilusTrader plans to support Python 3.14 for all officially supported platforms.

Current blockers:

• msgspec not available for Python 3.14 yet and cannot build from source on Windows in CI
• dydx extras include coincurve due to upstream coincurve compatibility (not available for Python 3.14 yet)
• ib (Interactive Brokers) extras include nautilus-ibapi which is not available for Python 3.14 yet

The dYdX and Interactive Brokers dependencies can be overcome with environment markers in the pyproject.toml.

The main blocker is msgspec, which is a core dependency used for all config objects (inheriting from msgspec.Struct). This affects all adapters and cannot be worked around for now.