agent v0.23.0: expose per-drive capacity (total/used/fraction) in GET /disks for the controller capacity bar

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

internal/localapi/disks.go

@@ -77,6 +77,10 @@ type DiskInfo struct {
 	Role          string `json:"role"`
 	DataBearing   bool   `json:"data_bearing"` // agent device-inspection verdict (UI hint)
 	DataReason    string `json:"data_reason,omitempty"`
+	// Capacity (from the agent's storage view) — for the controller's capacity bar. 0 when unknown.
+	TotalBytes   int64   `json:"total_bytes"`
+	UsedBytes    int64   `json:"used_bytes"`
+	UsedFraction float64 `json:"used_fraction"`
 	// DurableID is the target's stable identity (e.g. "uuid:<fs-uuid>" for usb/local-dir). The
 	// controller strips the "uuid:" prefix to get the fs UUID it passes to POST /disks/assign —
 	// the only way the (de-privileged) controller can learn the mount key it cannot read itself.
@@ -104,6 +108,9 @@ func (s *Server) handleDisks(w http.ResponseWriter, r *http.Request, vmid int) {
 			BackingDevice: t.BackingDevice, MountPath: t.MountPath, Class: t.ClassHint,
 			DurableID:    t.DurableID,
 			Role:         string(storage.RoleForStorage(t.Type, t.BackingDevice, sysDisks, sysKnown)),
+			TotalBytes:   t.TotalBytes,
+			UsedBytes:    t.UsedBytes,
+			UsedFraction: t.UsedFraction,
 		}
 		// Inspect the backing device for the UI's data-bearing hint (the authoritative check
 		// is re-run at format time on the actual device).