Initial implementation: host lifecycle + PXE + admin dashboard

Go service for Proxmox homelab cluster provisioning. Handles PXE boot,
Proxmox autoinstall (answer file generation), cluster join via SSH,
and Infrastructure API registration.

- Host state machine (registered → pxe_ready → installing → ready)
- dnsmasq supervisor with MAC-based allowlist
- iPXE script and Proxmox answer file generation
- First-boot phone-home → cluster join → infra registration
- Operation locking with expiry (409 on conflict)
- SSE event hub for real-time dashboard updates
- Admin dashboard (host grid, detail, registration form)
- Config-driven server types with hot-reload
- Docker deployment (multi-stage fat image)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/orchestrator/host.go

@@ -0,0 +1,111 @@
+package orchestrator
+
+import (
+	"context"
+	"log"
+
+	"provisioning/internal/config"
+	"provisioning/internal/infra"
+	"provisioning/internal/model"
+	"provisioning/internal/statemachine"
+	"provisioning/internal/store"
+)
+
+type HostOrchestrator struct {
+	Runner      *Runner
+	Hosts       *store.Hosts
+	Ops         *store.Operations
+	Locks       *store.Locks
+	Cluster     *ClusterJoiner
+	InfraClient *infra.Client
+	Config      *config.Config
+	ServerTypes *config.ServerTypeRegistry
+}
+
+func (o *HostOrchestrator) HandlePhoneHome(ctx context.Context, hostID int64, ip string, hardwareID string) {
+	if err := o.Hosts.UpdateIP(ctx, hostID, ip, hardwareID); err != nil {
+		log.Printf("host %d: failed to update IP: %v", hostID, err)
+		o.Runner.FailHost(ctx, hostID, "failed to update IP: "+err.Error())
+		return
+	}
+
+	if _, err := o.Runner.Transition(ctx, hostID, statemachine.TriggerPhoneHome); err != nil {
+		log.Printf("host %d: phone-home transition failed: %v", hostID, err)
+		return
+	}
+
+	go o.postPhoneHome(hostID, ip, hardwareID)
+}
+
+func (o *HostOrchestrator) postPhoneHome(hostID int64, ip string, hardwareID string) {
+	ctx := context.Background()
+
+	host, err := o.Hosts.Get(ctx, hostID)
+	if err != nil {
+		log.Printf("host %d: failed to get host for cluster join: %v", hostID, err)
+		o.Runner.FailHost(ctx, hostID, "get host: "+err.Error())
+		return
+	}
+
+	if _, err := o.Runner.Transition(ctx, hostID, statemachine.TriggerClusterJoinStart); err != nil {
+		log.Printf("host %d: cluster join start transition failed: %v", hostID, err)
+		return
+	}
+
+	if err := o.Cluster.Join(ctx, ip); err != nil {
+		log.Printf("host %d: cluster join failed: %v", hostID, err)
+		o.Runner.FailHost(ctx, hostID, "cluster join: "+err.Error())
+		return
+	}
+
+	if err := o.registerInfra(ctx, host, ip, hardwareID); err != nil {
+		log.Printf("host %d: infra registration failed: %v", hostID, err)
+		o.Runner.FailHost(ctx, hostID, "infra registration: "+err.Error())
+		return
+	}
+
+	if _, err := o.Runner.Transition(ctx, hostID, statemachine.TriggerJoinComplete); err != nil {
+		log.Printf("host %d: join complete transition failed: %v", hostID, err)
+		return
+	}
+
+	op, err := o.Ops.GetActive(ctx, hostID)
+	if err == nil {
+		_ = o.Ops.Complete(ctx, op.ID)
+	}
+	_ = o.Locks.Release(ctx, hostID)
+	log.Printf("host %d (%s): provisioning complete", hostID, host.Hostname)
+}
+
+func (o *HostOrchestrator) registerInfra(ctx context.Context, host *model.Host, ip string, hardwareID string) error {
+	if o.InfraClient == nil {
+		return nil
+	}
+
+	st, _ := o.ServerTypes.Get(host.ServerType)
+	serverTypeID := o.Config.Infrastructure.ServerTypeMap[host.ServerType]
+
+	infraID, err := o.InfraClient.CreateHost(ctx, infra.CreateHostRequest{
+		HardwareID:   hardwareID,
+		Hostname:     host.Hostname,
+		AssetID:      host.Hostname,
+		RoomID:       o.Config.Infrastructure.RoomID,
+		ServerTypeID: serverTypeID,
+	})
+	if err != nil {
+		return err
+	}
+
+	if err := o.Hosts.UpdateInfraID(ctx, host.ID, infraID); err != nil {
+		return err
+	}
+
+	_ = o.InfraClient.CreateInterface(ctx, infra.CreateInterfaceRequest{
+		HostID:     int(infraID),
+		Name:       st.ManagementNIC,
+		MACAddress: host.MAC,
+		IPAddress:  ip,
+	})
+
+	return nil
+}