[srp-client] exclude non-preferred addresses in AutoAddress mode (#9642)

This commit updates the `AutoAddress` mode in `Srp::Client` to
exclude any deprecated (non-preferred) address when registering
host addresses.

It also updates `test_srp_auto_host_address` to validate the new
behavior.

tests/scripts/thread-cert/node.py

@@ -1880,8 +1880,8 @@ class NodeImpl:
         self.send_command(cmd)
         self._expect_done()
 
-    def get_addrs(self):
-        self.send_command('ipaddr')
+    def get_addrs(self, verbose=False):
+        self.send_command('ipaddr' + (' -v' if verbose else ''))
 
         return self._expect_results(r'\S+(:\S*)+')
 

tests/scripts/thread-cert/test_srp_auto_host_address.py

@@ -155,6 +155,19 @@ class SrpAutoHostAddress(thread_cert.TestCase):
         self.assertEqual(len(slaac_addr), 1)
         self.check_registered_addresses(client, server)
 
+        #-------------------------------------------------------------------
+        # Add a non-preferred SLAAC on-mesh prefix and check that the
+        # set of registered addresses remains unchanged and that the
+        # non-preferred  address is not registered by SRP client.
+
+        client.add_prefix('fd00:a:b:c::/64', 'aos')
+        client.register_netdata()
+        self.simulator.go(5)
+
+        slaac_addr = [addr.strip() for addr in client.get_addrs() if addr.strip().startswith('fd00:a:b:c:')]
+        self.assertEqual(len(slaac_addr), 1)
+        self.check_registered_addresses(client, server)
+
         #-------------------------------------------------------------------
         # Remove the on-mesh prefix (which will trigger an address to be
         # removed) and check that the SRP client re-registered and updated
@@ -219,19 +232,21 @@ class SrpAutoHostAddress(thread_cert.TestCase):
         # Check the host addresses on server to match client.
 
         host_addresses = [addr.strip() for addr in server_host['addresses']]
-        client_addresses = [addr.strip() for addr in client.get_addrs()]
+
+        client_mleid = client.get_mleid()
+        client_addresses = [addr.split(' ')[0] for addr in client.get_addrs(verbose=True) if 'preferred:1' in addr]
+        client_addresses += [client_mleid]
 
         # All registered addresses must be in client list of addresses.
 
         for addr in host_addresses:
             self.assertIn(addr, client_addresses)
 
-        # All addresses on client excluding link-local and mesh-local
-        # addresses must be seen on server side. But if there was
-        # no address, then mesh-local address should be the only
+        # All preferred addresses on client excluding link-local and
+        # mesh-local addresses must be seen on server side. But if there
+        # was no address, then mesh-local address should be the only
         # one registered.
 
-        client_mleid = client.get_mleid()
         checked_address = False
 
         for addr in client_addresses: