slice 8C Phase B.2 + C.1/C.2: retire disk subsystem + rewire disk mgmt to agent

Retired (~12.3k LOC): internal/storage/* (scan/format/attach/migrate/safety),
backup restic/crossdrive/restore_drives/disk_layout/local_infra/restore_scan/
paths + restore_app, report/infra_backup*/infra_pull, setup/scanner,
monitor/watchdog+pinger, web/storage_handlers+handler_restore. Surgically split
backup.Manager to app-data only (DB dumps + volume tars + app restore; dropped
restic + cross-drive + snapshot history). Fixed router/main/web wiring.
Added agent-backed disk API (web/agent_disk_handlers.go): /api/disks list/
assign/eject/format proxying agentapi; data-bearing format refusal -> HTTP 409
'operator authorization required'. report/config_pull.go keeps the setup
fresh-install config download. go build + go test green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

controller/internal/report/config_pull.go

@@ -0,0 +1,61 @@
+package report
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+)
+
+// Config-pull error types for setup-wizard UI display.
+//
+// These (and PullConfig) were previously part of infra_pull.go alongside the
+// disk-tier DR-recovery (PullRecovery / infra-backup) client. Disk recovery moved
+// to the host agent in slice 8C; only the fresh-install config download survives
+// here, so it lives in this slimmed file.
+var (
+	ErrHubUnreachable = errors.New("hub unreachable")
+	ErrAuthFailed     = errors.New("authentication failed")
+	ErrNotFound       = errors.New("customer not found")
+	ErrHubError       = errors.New("hub error")
+)
+
+// PullConfig fetches a generated controller.yaml from the Hub config endpoint.
+// Auth: X-Retrieval-Password header. Used by the setup wizard's fresh-install flow.
+func PullConfig(hubURL, customerID, retrievalPassword string) (string, error) {
+	url := strings.TrimRight(hubURL, "/") + "/api/v1/config/" + customerID
+
+	client := &http.Client{Timeout: 30 * time.Second}
+
+	req, err := http.NewRequest(http.MethodGet, url, nil)
+	if err != nil {
+		return "", fmt.Errorf("%w: %v", ErrHubError, err)
+	}
+	req.Header.Set("X-Retrieval-Password", retrievalPassword)
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return "", fmt.Errorf("%w: %v", ErrHubUnreachable, err)
+	}
+	defer resp.Body.Close()
+
+	switch resp.StatusCode {
+	case http.StatusOK:
+		// success
+	case http.StatusUnauthorized:
+		return "", ErrAuthFailed
+	case http.StatusNotFound:
+		return "", ErrNotFound
+	default:
+		return "", fmt.Errorf("%w: HTTP %d", ErrHubError, resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(io.LimitReader(resp.Body, 1<<20)) // 1MB limit
+	if err != nil {
+		return "", fmt.Errorf("%w: reading response: %v", ErrHubError, err)
+	}
+
+	return string(body), nil
+}