[client] Move mgmt cache pending-resolve test helpers to export_test.go

WaitForPendingResolves and pendingCount existed only to let tests wait
for the background initial resolves; they had no production caller. Keep
the production API surface clean by moving them into export_test.go
(unexported, test-build only) as waitForPendingResolves/pendingCount.

client/internal/dns/mgmt/export_test.go

@@ -0,0 +1,25 @@
+package mgmt
+
+import "time"
+
+// pendingCount returns the number of domains whose initial resolve is still in
+// flight. Test-only: lets tests wait for background resolves kicked off by
+// UpdateFromServerDomains.
+func (m *Resolver) pendingCount() int {
+	m.mutex.RLock()
+	defer m.mutex.RUnlock()
+	return len(m.pending)
+}
+
+// waitForPendingResolves blocks until all background initial resolves have
+// settled, or the timeout elapses. Returns true if all settled. Test-only.
+func (m *Resolver) waitForPendingResolves(timeout time.Duration) bool {
+	deadline := time.Now().Add(timeout)
+	for m.pendingCount() > 0 {
+		if time.Now().After(deadline) {
+			return false
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+	return true
+}

client/internal/dns/mgmt/mgmt.go

@@ -619,30 +619,6 @@ func (m *Resolver) clearPending(dnsName string) {
 	m.mutex.Unlock()
 }
 
-// pendingCount returns the number of domains whose initial resolve is still in
-// flight. Primarily useful for tests that need to wait for background resolves
-// kicked off by UpdateFromServerDomains.
-func (m *Resolver) pendingCount() int {
-	m.mutex.RLock()
-	defer m.mutex.RUnlock()
-	return len(m.pending)
-}
-
-// WaitForPendingResolves blocks until all background initial resolves kicked
-// off by UpdateFromServerDomains have settled, or the timeout elapses. It
-// returns true if all settled. Intended for tests and shutdown paths that need
-// the cache populated synchronously.
-func (m *Resolver) WaitForPendingResolves(timeout time.Duration) bool {
-	deadline := time.Now().Add(timeout)
-	for m.pendingCount() > 0 {
-		if time.Now().After(deadline) {
-			return false
-		}
-		time.Sleep(10 * time.Millisecond)
-	}
-	return true
-}
-
 // awaitPendingResolve waits for an in-flight initial resolve of dnsName to
 // finish, bounded by dnsTimeout. It joins the existing resolveGroup flight so
 // concurrent ServeDNS waiters share one resolution. Returns true if a record

client/internal/dns/mgmt/mgmt_test.go

@@ -329,7 +329,7 @@ func TestResolver_ManagementDomainProtection(t *testing.T) {
 	if err != nil {
 		t.Logf("Server domains update failed: %v", err)
 	}
-	resolver.WaitForPendingResolves(10 * time.Second)
+	resolver.waitForPendingResolves(10 * time.Second)
 
 	finalDomains := resolver.GetCachedDomains()
 
@@ -367,7 +367,7 @@ func TestResolver_EmptyUpdateDoesNotRemoveDomains(t *testing.T) {
 	if err != nil {
 		t.Skipf("Skipping test due to DNS resolution failure: %v", err)
 	}
-	resolver.WaitForPendingResolves(10 * time.Second)
+	resolver.waitForPendingResolves(10 * time.Second)
 
 	// Verify domains were added
 	cachedDomains := resolver.GetCachedDomains()
@@ -402,7 +402,7 @@ func TestResolver_PartialUpdateReplacesOnlyUpdatedTypes(t *testing.T) {
 	if err != nil {
 		t.Skipf("Skipping test due to DNS resolution failure: %v", err)
 	}
-	resolver.WaitForPendingResolves(10 * time.Second)
+	resolver.waitForPendingResolves(10 * time.Second)
 	assert.Len(t, resolver.GetCachedDomains(), 3)
 
 	// Update with partial ServerDomains (only signal domain - this should replace signal but preserve stun/turn)
@@ -413,7 +413,7 @@ func TestResolver_PartialUpdateReplacesOnlyUpdatedTypes(t *testing.T) {
 	if err != nil {
 		t.Skipf("Skipping test due to DNS resolution failure: %v", err)
 	}
-	resolver.WaitForPendingResolves(10 * time.Second)
+	resolver.waitForPendingResolves(10 * time.Second)
 
 	// Should remove only the old signal domain
 	assert.Len(t, removedDomains, 1, "Should remove only the old signal domain")
@@ -448,7 +448,7 @@ func TestResolver_PartialUpdateAddsNewTypePreservesExisting(t *testing.T) {
 	if err != nil {
 		t.Skipf("Skipping test due to DNS resolution failure: %v", err)
 	}
-	resolver.WaitForPendingResolves(10 * time.Second)
+	resolver.waitForPendingResolves(10 * time.Second)
 	assert.Len(t, resolver.GetCachedDomains(), 3)
 
 	// Update with partial ServerDomains (only flow domain - flow is intentionally excluded from
@@ -460,7 +460,7 @@ func TestResolver_PartialUpdateAddsNewTypePreservesExisting(t *testing.T) {
 	if err != nil {
 		t.Skipf("Skipping test due to DNS resolution failure: %v", err)
 	}
-	resolver.WaitForPendingResolves(10 * time.Second)
+	resolver.waitForPendingResolves(10 * time.Second)
 
 	assert.Len(t, removedDomains, 0, "Should not remove any domains when only flow domain is provided")