all: apply golangci-lint 2.9.0 fixes

Fix issues found by the upgraded golangci-lint:
- wsl_v5: add required whitespace in CLI files
- staticcheck SA4006: replace new(var.Field) with &localVar
  pattern since staticcheck does not recognize Go 1.26
  new(value) as a use of the variable
- staticcheck SA5011: use t.Fatal instead of t.Error for
  nil guard checks so execution stops
- unused: remove dead ptrTo helper function

integration/helpers.go

@@ -929,8 +929,8 @@ func tagp(name string) policyv2.Alias {
 // prefixp returns a pointer to a Prefix from a CIDR string for policy v2 configurations.
 // Converts CIDR notation to policy prefix format for network range specifications.
 func prefixp(cidr string) policyv2.Alias {
-	prefix := netip.MustParsePrefix(cidr)
-	return new(policyv2.Prefix(prefix))
+	p := policyv2.Prefix(netip.MustParsePrefix(cidr))
+	return &p
 }
 
 // aliasWithPorts creates an AliasWithPorts structure from an alias and port ranges.