Show Seed Vault names for temporary seeds

### releases/Next-ChangeLog.md
@@ -19,6 +19,9 @@ your addition and anything else already in this file.**
   malformed global input/output count encodings, and files missing the required
   global version.
 
+- Enhancement: Optionally show Seed Vault names for temporary seed fingerprints
+  at the top of the home menu.
+
 
 # Mk Specific Changes
 

### shared/actions.py
@@ -994,6 +994,19 @@ def make_top_menu():
                 sl, sr = ("[", "]") if pa.tmp_value else ("<", ">")
                 if active_xfp:
                     ui_xfp = sl + xfp2str(active_xfp) + sr
+                    if pa.tmp_value and settings.master_get("tsn", False):
+                        from seed import seed_vault_iter
+                        from utils import deserialize_secret
+
+                        for rec in seed_vault_iter():
+                            if deserialize_secret(rec.encoded) != pa.tmp_value:
+                                continue
+
+                            named_xfp = "[" + rec.label + "]"
+                            max_name_width = 32 if version.has_qwerty else 16
+                            if len(named_xfp) <= max_name_width:
+                                ui_xfp = named_xfp
+                            break
                     _cls.insert(0, MenuItem(ui_xfp, f=ready2sign))
                 if pa.tmp_value:
                     _cls.append(MenuItem("Restore Master", f=restore_main_secret, shortcut='m'))

### shared/flow.py
@@ -175,6 +175,12 @@ async def goto_home(*a):
                           'Master seed is displayed as <XFP>, temporary seeds as [XFP].'),
                    predicate=has_real_secret,
                    on_change=goto_home),
+    ToggleMenuItem('Temporary Seed Names', 'tsn', ['Use XFP', 'Use Names'],
+                   story=("Show a temporary seed's Seed Vault name instead of its XFP "
+                          "at the top of the home menu. If the name is too long to "
+                          "fit, the XFP is shown."),
+                   predicate=has_real_secret,
+                   on_change=goto_home),
     ToggleMenuItem('Menu Wrapping', 'wa', ['Default', 'Always Wrap'],
            story='''When enabled, allows scrolling past menu top/bottom \
 (wrap around). By default, this only happens in menus whose length is greater than 10.'''),

### shared/nvstore.py
@@ -63,6 +63,7 @@
 #   b85max = (bool) allow max BIP-32 int value in BIP-85 derivations
 #   ptxurl = (str) URL for PushTx feature, clear to disable feature
 #   hmx    = (bool) Force display of current XFP in home menu, even w/o tmp seed active
+#   tsn    = (bool) Use Seed Vault names for temporary seed XFPs in home menu
 #   unsort_ms = (bool) Allow unsorted multisig with BIP-67 disabled
 #   msas = multisig address show (do not censor multisig addresses)
 #   ccc = (complex) If present, CCC feature is enabled and key details stored here.
@@ -95,7 +96,7 @@
 
 # key value pairs saved directly to master seed settings
 # held in RAM for tmp seed sessions
-MASTER_FIELDS = ['seeds', 'seedvault', 'xfp', 'words', "bkpw", "sssp"]
+MASTER_FIELDS = ['seeds', 'seedvault', 'xfp', 'words', "bkpw", "sssp", "tsn"]
 
 NUM_SLOTS = const(100)
 SLOTS = range(NUM_SLOTS)

### testing/test_ephemeral.py
@@ -1703,9 +1703,11 @@ def test_import_master_as_tmp(reset_seed_words, goto_eph_seed_menu, cap_story,
     story, parsed_ident = get_identity_story()
     assert xfp_str == parsed_ident["xfp"]
 
-def test_home_menu_xfp(goto_home, pick_menu_item, press_select, cap_story, cap_menu,
+@pytest.mark.parametrize('name_fits', [True, False])
+def test_home_menu_xfp(name_fits, goto_home, pick_menu_item, press_select, cap_story, cap_menu,
                        settings_get, goto_eph_seed_menu, need_keypress,
-                       enter_mash_entropy):
+                       enter_mash_entropy, master_settings_get, sim_exec,
+                       has_qwerty):
     goto_home()
     pick_menu_item("Settings")
     pick_menu_item("Buried Settings")
@@ -1738,7 +1740,34 @@ def test_home_menu_xfp(goto_home, pick_menu_item, press_select, cap_story, cap_m
     time.sleep(.2)
     m = cap_menu()
     assert m[1] == "Ready To Sign"
-    assert m[0] == "[" + xfp2str(settings_get("xfp")) + "]"
+    tmp_xfp = xfp2str(settings_get("xfp"))
+    assert m[0] == "[" + tmp_xfp + "]"
+
+    original_seeds = master_settings_get("seeds") or []
+    original_tsn = master_settings_get("tsn")
+    sim_exec("from seed import SecretStash; from pincodes import pa; "
+             "encoded = SecretStash.storage_serialize(pa.tmp_value); "
+             "settings.master_set('seeds', %r + [(%r, encoded, 'Travel', 'test')]); "
+             "settings.master_set('tsn', True)" % (original_seeds, tmp_xfp))
+    goto_home()
+    assert cap_menu()[0] == "[Travel]"
+
+    max_name_width = 32 if has_qwerty else 16
+    name_width = max_name_width - 2 + (not name_fits)
+    test_name = 'N' * name_width
+    sim_exec("from seed import SecretStash; from pincodes import pa; "
+             "encoded = SecretStash.storage_serialize(pa.tmp_value); "
+             "settings.master_set('seeds', %r + [(%r, encoded, %r, 'test')])" %
+             (original_seeds, tmp_xfp, test_name))
+    goto_home()
+    expected_name = "[" + test_name + "]" if name_fits else "[" + tmp_xfp + "]"
+    assert cap_menu()[0] == expected_name
+
+    sim_exec("settings.master_set('seeds', %r); settings.master_set('tsn', %r)" %
+             (original_seeds, original_tsn))
+    goto_home()
+    assert cap_menu()[0] == "[" + tmp_xfp + "]"
+
     pick_menu_item("Restore Master")
     press_select()
 
@@ -1761,7 +1790,6 @@ def test_home_menu_xfp(goto_home, pick_menu_item, press_select, cap_story, cap_m
     m = cap_menu()
     assert m[0] == "Ready To Sign"
 
-
 def test_seed_vault_enable_on_tmp(generate_ephemeral_words, reset_seed_words,
                                   goto_eph_seed_menu, ephemeral_seed_disabled,
                                   verify_ephemeral_secret_ui, goto_home, cap_menu,