test(odoh): integration-verify relay_ip/target_ip override wiring

Suite 8 now ends with a config using RFC 5737 TEST-NET-1 IPs as
relay_ip/target_ip, started briefly so the bootstrap resolver logs its
override map. Asserts both host=IP pairs land in that map — closing the
gap flagged on PR #126 (zero-plain-DNS-leak for ODoH endpoints was only
unit-tested).

Also: NumaResolver::new now logs the override map at INFO when non-empty,
so operators can verify their ODoH bootstrap without needing DEBUG level.

src/bootstrap_resolver.rs

@@ -70,6 +70,17 @@ impl NumaResolver {
             ips.join(", "),
             source
         );
+        if !overrides.is_empty() {
+            let mut pairs: Vec<String> = overrides
+                .iter()
+                .flat_map(|(host, ips)| ips.iter().map(move |ip| format!("{}={}", host, ip)))
+                .collect();
+            pairs.sort();
+            info!(
+                "bootstrap resolver: host overrides (skip DNS, connect direct): {}",
+                pairs.join(", ")
+            );
+        }
         Self {
             bootstrap,
             overrides,