reconcile: tier-aware restore-task deadline (S4.1 unattended offsite restore-test)

A WAN (pbs-tier) restore of a large guest exceeds the restore-task wait's 10m
default → the wait expired mid-restore, teardown fired against a still-restoring
(not-yet-pool-associated) scratch guest → leak + a phantom VM.Allocate 403.

- RestoreTestSpec.RestoreTaskTimeout (0→10m default); the restore WaitTask passes
  it. Local tier unchanged (10m).
- config RestoreTestPBSRestoreTimeoutSeconds + accessor (default 120m).
- main restoreTaskTimeout(cfg,tier): configured PBS timeout only when tier==pbs,
  else 0. Both scheduler + selftest spec builds.
- Tests + WaitOptions red-proof + accessor contract.

The "grant scratch-band VM.Allocate" follow-up is diagnosed not blind-applied:
the scratch is restored INTO /pool/felhom (ACL already grants VM.Allocate), so
the earlier 403 was a consequence of the timeout. No ACL/host-install change.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PSK5g6qYLknKj8u3QAFEr6

internal/config/config_test.go

@@ -5,8 +5,29 @@ import (
 	"path/filepath"
 	"strings"
 	"testing"
+	"time"
 )
 
+// TestRestoreTestPBSRestoreTimeout mirrors the BackupCadence accessor contract: positive as-is,
+// 0 → default (120m), negative → default.
+func TestRestoreTestPBSRestoreTimeout(t *testing.T) {
+	cases := []struct {
+		secs int
+		want time.Duration
+	}{
+		{0, 120 * time.Minute},
+		{-5, 120 * time.Minute},
+		{1800, 30 * time.Minute},
+		{7200, 120 * time.Minute},
+	}
+	for _, c := range cases {
+		got := BackupConfig{RestoreTestPBSRestoreTimeoutSeconds: c.secs}.RestoreTestPBSRestoreTimeout()
+		if got != c.want {
+			t.Errorf("RestoreTestPBSRestoreTimeout(secs=%d) = %v, want %v", c.secs, got, c.want)
+		}
+	}
+}
+
 func TestRedactedMasksSecret(t *testing.T) {
 	c := Default()
 	c.Proxmox.Token = "felhom-agent@pve!agent=b6547d9d-08ec-4f22-beb8-a551dc2cd69d"