bolt11: remove tag arg from get_routing_info

### electrum/bolt11.py
@@ -328,8 +328,8 @@ def get_amount_sat(self) -> Optional[Decimal]:
             return None
         return self.amount * COIN
 
-    def get_routing_info(self, tag):
-        r_tags = list(filter(lambda x: x[0] == tag, self.tags))
+    def get_routing_info(self):
+        r_tags = list(filter(lambda x: x[0] == 'r', self.tags))
         # strip the tag type, it's implicitly 'r' now
         r_tags = list(map(lambda x: x[1], r_tags))
         # if there are multiple hints, we will use the first one that works,
@@ -427,7 +427,7 @@ def to_debug_json(self) -> Dict[str, Any]:
             'tags': self.tags,
             'unknown_tags': self.unknown_tags,
         }
-        if ln_routing_info := self.get_routing_info('r'):
+        if ln_routing_info := self.get_routing_info():
             d['r_tags'] = self.format_bolt11_routing_info_as_human_readable(ln_routing_info)
         return d
 

### electrum/gui/qml/qeinvoice.py
@@ -275,7 +275,7 @@ def set_lnprops(self):
             return
 
         lnaddr = self._effectiveInvoice._lnaddr
-        ln_routing_info = lnaddr.get_routing_info('r')
+        ln_routing_info = lnaddr.get_routing_info()
         self._logger.debug(str(ln_routing_info))
 
         self._lnprops = {

### electrum/gui/qt/main_window.py
@@ -1718,7 +1718,7 @@ def show_lightning_invoice(self, invoice: Invoice):
         invoice_e.setText(invoice.lightning_invoice)
         grid.addWidget(QLabel(_('Text') + ':'), 8, 0)
         grid.addWidget(invoice_e, 8, 1)
-        r_tags = lnaddr.get_routing_info('r')
+        r_tags = lnaddr.get_routing_info()
         r_tags = '\n'.join(repr(r) for r in BOLT11Addr.format_bolt11_routing_info_as_human_readable(r_tags))
         routing_e = QTextEdit(str(r_tags))
         routing_e.setReadOnly(True)

### electrum/lnworker.py
@@ -1969,7 +1969,7 @@ async def pay_invoice(
         payment_secret = lnaddr.payment_secret
         invoice_pubkey = lnaddr.pubkey.serialize()
         invoice_features = lnaddr.get_features()
-        r_tags = lnaddr.get_routing_info('r')
+        r_tags = lnaddr.get_routing_info()
         amount_to_pay = lnaddr.get_amount_msat()
         status = self.get_invoice_status(invoice)
         if status == PR_PAID:

### tests/lnhelpers.py
@@ -285,7 +285,7 @@ async def create_routes_from_invoice(self, amount_msat: int, decoded_invoice: BO
             payment_secret=decoded_invoice.payment_secret,
             initial_trampoline_fee_level=0,
             invoice_features=decoded_invoice.get_features(),
-            r_tags=decoded_invoice.get_routing_info('r'),
+            r_tags=decoded_invoice.get_routing_info(),
             min_final_cltv_delta=decoded_invoice.get_min_final_cltv_delta(),
             amount_to_pay=amount_msat,
             invoice_pubkey=decoded_invoice.pubkey.serialize(),

### tests/test_bolt11.py
@@ -277,7 +277,7 @@ def test_tag_padding_errors(self):
         # control: a well-formed hop is parsed
         r_hop = bytes(33) + bytes(8) + (1).to_bytes(4, 'big') + (2).to_bytes(4, 'big') + (3).to_bytes(2, 'big')
         invoice = self._encode_invoice_with_raw_tag('r', list(convertbits(r_hop, 8, 5)))
-        self.assertEqual(1, len(decode_bolt11_invoice(invoice).get_routing_info('r')))
+        self.assertEqual(1, len(decode_bolt11_invoice(invoice).get_routing_info()))
 
     def test_invalid_signature(self):
         # The trailing 65 bytes of an invoice are attacker-controlled: every way the ecc lib

### tests/test_lnwallet.py
@@ -160,7 +160,7 @@ async def test_trampoline_invoice_features_and_routing_hints(self):
         )
 
         lnaddr, _ = wallet.get_bolt11_invoice(payment_info=pi, message='test', fallback_address=None)
-        hint_node_ids = {route[0][0] for route in lnaddr.get_routing_info('r')}
+        hint_node_ids = {route[0][0] for route in lnaddr.get_routing_info()}
         self.assertEqual(hint_node_ids, {trampoline_pubkey, regular_pubkey})
 
         # trampoline feature should not be set if we use trampoline but one peer is not a trampoline
@@ -176,7 +176,7 @@ async def test_trampoline_invoice_features_and_routing_hints(self):
 
         wallet.clear_invoices_cache()
         lnaddr, _ = wallet.get_bolt11_invoice(payment_info=pi, message='test', fallback_address=None)
-        hint_node_ids = {route[0][0] for route in lnaddr.get_routing_info('r')}
+        hint_node_ids = {route[0][0] for route in lnaddr.get_routing_info()}
         self.assertEqual(hint_node_ids, {trampoline_pubkey, regular_pubkey})
 
         wallet.uses_trampoline = old_check
@@ -198,14 +198,14 @@ async def test_trampoline_invoice_features_and_routing_hints(self):
 
         wallet.clear_invoices_cache()
         lnaddr2, _ = wallet.get_bolt11_invoice(payment_info=pi2, message='test', fallback_address=None)
-        hint_node_ids2 = {route[0][0] for route in lnaddr2.get_routing_info('r')}
+        hint_node_ids2 = {route[0][0] for route in lnaddr2.get_routing_info()}
         self.assertEqual(hint_node_ids2, {trampoline_pubkey, regular_pubkey})
 
         # assert only trampoline peers are included in r_tags if the invoice_features signal trampoline
         del electrum.trampoline._TRAMPOLINE_NODES_UNITTESTS['regular_peer']
         wallet.clear_invoices_cache()
         lnaddr3, _ = wallet.get_bolt11_invoice(payment_info=pi2, message='test', fallback_address=None)
-        hint_node_ids3 = {route[0][0] for route in lnaddr3.get_routing_info('r')}
+        hint_node_ids3 = {route[0][0] for route in lnaddr3.get_routing_info()}
         self.assertEqual(hint_node_ids3, {trampoline_pubkey})
 
     async def test_open_channel_just_in_time_success(self):