Add `config.trace_context_names` for better cache miss messages.
This change introduces `jaxlib.config.trace_context_names`, which returns the names of the configuration values included in the JAX tracing context. This is used in `partial_eval.py` to provide more detailed explanations when a cache miss occurs due to differences in the tracing context, specifying which named config values have changed. The new functionality is guarded by a jaxlib version check.
PiperOrigin-RevId: 917195862
