fix: thread subnet into orchestrator to prevent port collisions

[qj0r9j0vc2]

Summary

• Provisioning a new devnet while another is running causes port collisions because the orchestrator creates nodes with empty Spec.Address, causing all nodes to bind to 0.0.0.0 on the same default ports (26657, 26656, etc.)
• Threads the allocated subnet through ProvisionOptions so initializeNode() sets node.Spec.Address to the correct loopback IP (e.g., 127.0.42.1), enabling configureNodeNetworking() to bind each devnet's nodes to unique IPs

Changes

• Added Subnet uint8 field to ProvisionOptions
• Passed allocatedSubnet through provisionWithOrchestrator() and devnetToProvisionOptions()
• Set node.Spec.Address via subnet.NodeIP() in initializeNode() when subnet > 0
• Updated test call sites for the changed function signature

Test Plan

• go build ./... passes
• go test ./internal/daemon/provisioner/... passes
• go test ./... full suite passes (0 failures)
• Deploy and provision two devnets simultaneously, verify nodes bind to different loopback IPs