Offer ActivityOptions via Supplier to support dynamic configs

Is your feature request related to a problem? Please describe.
Tuning activity timeouts in workflows involves rebuilding and deploying an application, which can be an unacceptably long turnaround time depending on the urgency of the timeout change (e.g. in response to an incident). Some workers may also have a long startup / awaitTermination cycle, so the current methodology of updating a dynamic config and then redeploying is also too long of a loop.

Describe the solution you'd like
ActivityOptions provided via WorkerImplementationOptions to support a Supplier<ActivityOptions> would help allow us to plugin a dynamic config store to update workers' activity options, specifically the timeouts, on a faster cycle.

Describe alternatives you've considered

• Changing the configs in code, redeploying
• Changing configs and then restarting the workers

Start by tracing how ActivityOptions supplied through WorkerImplementationOptions are consumed in the Java SDK. Review the option-handling entry points and existing tests, then verify that a Supplier can provide updated activity timeouts without rebuilding or restarting workers.