fix(ui): one rule for value rows, one meaning for Hold Enter

Three interaction inconsistencies found while auditing the favourites work,
all of the same shape: the same gesture meaning different things depending
on which screen you were on.

Value rows in popup menus. Rows like "Notif: ON" or "Sort: Dist" show a
value the user steps through with LEFT/RIGHT, but Enter treated them as
ordinary menu picks and closed the popup, so changing two of them meant
reopening the menu in between. Trail's settings submenu was the lone
exception, working around it by rebuilding and re-selecting after each
Enter. PopupMenu now knows the difference: addValueItem() marks a row, and
Enter on it returns the new VALUE_NEXT instead of SELECTED, leaving the
menu open. Only Back closes a menu now. Applied to the Messages
contact/room/channel menus, Nodes, the Ringtone editor and Trail, which
drops its reopenSettingsAt() workaround. The LEFT/RIGHT cycling bodies
moved into one helper per menu, since Enter and RIGHT now share them.

Nodes' Fav row was the worst case: LEFT/RIGHT did nothing there at all, so
the only way to toggle a favourite was an Enter that dismissed the menu on
every flip. Its label moved to a member buffer (as the Pin row already had)
so it can be retitled in place.

Settings rows Auto-off, Low battery, GPS pwr and Battery ignored Enter,
though their options wrap exactly like the melody/keyboard/clock rows
beside them, where Enter has always stepped forward. They accept it now.
Rows that ramp between fixed ends (Brightness, Volume, TX Pwr, Timezone,
SF/BW/CR) stay LEFT/RIGHT-only -- there is nothing to wrap to.

Hold Enter no longer doubles as Back. It quietly meant "go back" on Tools,
Locator, Live Share, Repeater, Bot, Auto-Advert, GPIO, Compass, the
Dashboard config and the Messages navigate view, while elsewhere the same
long press opens a context menu. It now only ever opens a menu, or does
nothing where there is none. Same for dismissing an open popup, which it
used to do. Checked that this strands nobody: every board that can reach
these screens has a real Back key (back_btn on joystick boards, Esc on
CardKB/TCA8418/T-Deck). Single-button boards produce no KEY_ENTER at all,
so they never leave the home pages in the first place.

docs/solo_features/tools_screen/tools_screen.md

@@ -41,10 +41,10 @@ Select a node to see its coordinates, distance, bearing with cardinal direction,
 | Ping                   | a public key is known for the node                                                     |
 | Save waypoint          | selected node has GPS                                                                   |
 | Set as target          | selected node has GPS **and** a public key — pins it as the active **Locator/Nav target** right away (see **Locator**) |
-| Fav: ON / OFF          | selected node is a saved contact — the same starred flag the Messages lists use, shared with the companion app |
+| Fav: ON / OFF          | selected node is a saved contact — **LEFT/RIGHT** or **Enter** toggles it in place, as in the Messages menus; the same starred flag those lists use, shared with the companion app |
 | Pin to dial / Unpin (slot N) | selected node is a saved contact — puts it on the [Favourites Dial](../favourites_dial/favourites_dial.md), taking the first free slot |
 | Admin                  | selected node is a saved **repeater or room server** contact — opens **Tools › Admin** for it directly (see **Admin**) |
-| Sort: Dist/Recent      | browsing stored nodes — **LEFT/RIGHT** on the row flips distance ↔ last-heard in place |
+| Sort: Dist/Recent      | browsing stored nodes — **LEFT/RIGHT** or **Enter** flips distance ↔ last-heard in place |
 | Discover scan / Rescan | always (live `NODE_DISCOVER_REQ` scan)                                                  |
 
 Filtering stays on the list itself (**LEFT/RIGHT** cycles the type), so there is no separate Filter action in the menu. **Sort** is adjusted in place: highlight the **Sort** row and tap **LEFT/RIGHT** to flip the list (and its right-hand column) between **distance** and **last-heard** without closing the menu — the same in-popup pattern as Trail's settings. The row appears only while browsing stored nodes (live-scan rows carry signal, not distance). Filter and sort are independent and **persist** across re-entry to the screen.
@@ -350,8 +350,8 @@ Each melody supports up to 32 notes:
 | ------------ | ----------- | -------------------------------------- |
 | Play / Stop  | Enter       | Preview the melody                     |
 | Melody 1 / 2 | Enter       | Switch to the other slot               |
-| Duration     | LEFT/RIGHT  | Cycle duration for selected note       |
-| BPM          | LEFT/RIGHT  | Cycle tempo                            |
+| Duration     | LEFT/RIGHT or Enter | Cycle duration for selected note |
+| BPM          | LEFT/RIGHT or Enter | Step tempo (stops at each end)  |
 | Insert       | Enter       | Insert a new note after the cursor     |
 | Delete       | Enter       | Delete the note at cursor              |
 | Save & Exit  | Enter       | Persist the melody and return to Tools |