Rewrite SF Compute provider to use sfc-go

[brianlechthaler]

Summary

• replace the SF Compute provider's old nodes-go integration with the new sfc-go SDK
• update instance creation to follow the preview resource model by managing nodes through a shared capacity + procurement pool per credential/stage/location
• switch Brev metadata persistence from encoded node names to node tags while preserving backward compatibility for legacy names
• add focused unit tests for tag metadata parsing, v2 status mapping, and preview-style cloud-init payload generation

Testing

• go test ./v1/providers/sfcompute/... ./v1/...

  

[semanticdiff-com]

Review changes with  

Changed Files

File	Status
v1/providers/sfcompute/client.go	46% smaller
v1/providers/sfcompute/instance.go	13% smaller
v1/providers/sfcompute/instancetype.go	6% smaller
go.mod	Unsupported file format
go.sum	Unsupported file format
v1/providers/sfcompute/instance_test.go	0% smaller
v1/providers/sfcompute/raw_api.go	0% smaller