[Feature Request][Go SDK]: Improve Native File IO Writes

### What would you like to happen?

The current Go SDK fileio doesn't behave properly WRT streaming writes.

Notionally we would need to at minimum take windows and panes into account. It should behave similarly to the Java and Python file sinks.

Similarly, there needs to be a reasonable approach for "dynamic destinations", whether that is based on string key infixes into a common location, or full destination path prefixes.

### Issue Priority

Priority: 3 (nice-to-have improvement)

### Issue Components

- [ ] Component: Python SDK
- [ ] Component: Java SDK
- [X] Component: Go SDK
- [ ] Component: Typescript SDK
- [ ] Component: IO connector
- [ ] Component: Beam examples
- [ ] Component: Beam playground
- [ ] Component: Beam katas
- [ ] Component: Website
- [ ] Component: Spark Runner
- [ ] Component: Flink Runner
- [ ] Component: Samza Runner
- [ ] Component: Twister2 Runner
- [ ] Component: Hazelcast Jet Runner
- [ ] Component: Google Cloud Dataflow Runner