feat(bot): room-server target, tab-carousel UI, per-target independence

Auto-Reply Bot gains a third target (room servers, alongside DM and
channel), new {name}/{hops} reply placeholders, and a DM all/favourites
allow-list. BotScreen is redesigned as a circular tab carousel (Direct /
Channel / Room / Other, same interaction as Nearby Nodes' filter tabs)
instead of one long scrolling list, which also exposed and fixed a
leftover coupling where Channel/Room trigger-replies and their !command
handling secretly depended on the DM tab's Enable/Commands toggles —
each target's Enable and Commands are now fully independent.

- NodePrefs: bot_room_enabled/prefix/trigger/reply, bot_dm_scope,
  bot_commands_ch/bot_commands_room (bot_commands_enabled repurposed as
  DM-only). SCHEMA_SENTINEL 0xC0DE001D -> 0xC0DE001F; sizeof unchanged
  at 2712 (new bytes absorbed existing padding, verified via a
  standalone host compile + offsetof check).
- DataStore: persists all new fields; seeds bot_commands_ch/room from
  the old shared bot_commands_enabled on upgrade so existing
  channel/room command behaviour isn't silently lost.
- MyMeshBot: tryBotReplyRoom/tryBotRoomCommand mirror the channel bot's
  shape but post via sendMessage (room relays to members itself);
  requires an existing login session with that room, same as a manual
  post would. botDmSenderAllowed() gates DM trigger-reply/commands on
  the favourites bit when bot_dm_scope=Fav.
- MsgExpand: {name}/{hops} as optional trailing params (default
  nullptr/-1, no existing caller affected) — deliberately not exposed
  on the general compose keyboard, only on bot Reply fields.
- QuickMsgScreen/UITask: room-target picker (mirrors the channel
  picker), routing through the existing room-login prompt when there's
  no saved password yet.
- BotScreen: tab carousel (LEFT/RIGHT switches tabs, UP/DOWN moves
  rows, Enter is now the only way to change a value); Enable split out
  of Channel/Room's combo row; Quiet Hours gained a stepper sub-mode;
  Commands moved from a shared toggle into each tab.
- docs/tools_screen.md updated for the new tab layout and behaviour.

Not build-verified — no PlatformIO toolchain in this environment.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

examples/companion_radio/DataStore.cpp

@@ -495,6 +495,31 @@ void DataStore::loadPrefsInt(const char *filename, NodePrefs& _prefs, double& no
   rd(&_prefs.keyboard_alt_alphabet, sizeof(_prefs.keyboard_alt_alphabet));
   if (_prefs.keyboard_alt_alphabet >= NodePrefs::KB_ALPHABET_COUNT) _prefs.keyboard_alt_alphabet = 0;
 
+  // → 0xC0DE001E: append bot_dm_scope + the room-server bot fields at the
+  // tail. A pre-0x1E file has the old sentinel bytes / EOF here; rd() zero-
+  // inits when absent, so upgraders default to bot_dm_scope=0 (all DMs,
+  // matching the original bot_enabled behaviour) and the room bot fully
+  // disabled (bot_room_enabled clamps to 0; an empty trigger never matches
+  // even if somehow set).
+  rd(&_prefs.bot_dm_scope, sizeof(_prefs.bot_dm_scope));
+  if (_prefs.bot_dm_scope > 1) _prefs.bot_dm_scope = 0;
+
+  rd(&_prefs.bot_room_enabled, sizeof(_prefs.bot_room_enabled));
+  if (_prefs.bot_room_enabled > 1) _prefs.bot_room_enabled = 0;
+  rd(_prefs.bot_room_prefix,  sizeof(_prefs.bot_room_prefix));
+  rd(_prefs.bot_trigger_room, sizeof(_prefs.bot_trigger_room));
+  rd(_prefs.bot_reply_room,   sizeof(_prefs.bot_reply_room));
+
+  // → 0xC0DE001F: split the shared bot_commands_enabled into a per-target
+  // toggle for channel/room too (DM keeps the original field). A pre-0x1F
+  // file has neither new byte; both clamp to 0 here and are seeded from the
+  // old shared value in the sentinel-mismatch migration below, so upgraders
+  // don't silently lose channel/room commands they already had answering.
+  rd(&_prefs.bot_commands_ch, sizeof(_prefs.bot_commands_ch));
+  if (_prefs.bot_commands_ch > 1) _prefs.bot_commands_ch = 0;
+  rd(&_prefs.bot_commands_room, sizeof(_prefs.bot_commands_room));
+  if (_prefs.bot_commands_room > 1) _prefs.bot_commands_room = 0;
+
   // Schema sentinel: bumped on layout changes. Mismatch means an older file
   // (or a different schema); rd() already zero-inits any fields not present,
   // so we just log it — next savePrefs writes the current sentinel.
@@ -518,6 +543,14 @@ void DataStore::loadPrefsInt(const char *filename, NodePrefs& _prefs, double& no
     if (sentinel < 0xC0DE0018 && _prefs.home_pages_mask != 0) {
       _prefs.home_pages_mask |= NodePrefs::HP_MAP;
     }
+    // 0xC0DE001E → 0xC0DE001F: bot_commands_enabled split per target (see the
+    // rd() above). Seed the two new fields from the old shared one so a
+    // pre-0x1F upgrader's channel/room commands keep answering exactly as
+    // before; gated to this transition so a user who later splits them apart
+    // isn't overridden on a later update.
+    if (sentinel < 0xC0DE001F) {
+      _prefs.bot_commands_ch = _prefs.bot_commands_room = _prefs.bot_commands_enabled;
+    }
     // 0xC0DE0003 → 0xC0DE0004: trail_units_idx added after trail_min_delta_idx.
     // On a 0xC0DE0003 file the sentinel bytes sit where trail_units_idx is now,
     // so rd() picks up 0x03 (low byte of the old sentinel) — reset just that
@@ -683,6 +716,13 @@ void DataStore::savePrefs(const NodePrefs& _prefs, double node_lat, double node_
     file.write((uint8_t *)&_prefs.trail_autosave_lowbatt, sizeof(_prefs.trail_autosave_lowbatt));
     file.write((uint8_t *)&_prefs.alarm_repeat_mask,      sizeof(_prefs.alarm_repeat_mask));
     file.write((uint8_t *)&_prefs.keyboard_alt_alphabet,  sizeof(_prefs.keyboard_alt_alphabet));
+    file.write((uint8_t *)&_prefs.bot_dm_scope,      sizeof(_prefs.bot_dm_scope));
+    file.write((uint8_t *)&_prefs.bot_room_enabled,  sizeof(_prefs.bot_room_enabled));
+    file.write((uint8_t *)_prefs.bot_room_prefix,    sizeof(_prefs.bot_room_prefix));
+    file.write((uint8_t *)_prefs.bot_trigger_room,   sizeof(_prefs.bot_trigger_room));
+    file.write((uint8_t *)_prefs.bot_reply_room,     sizeof(_prefs.bot_reply_room));
+    file.write((uint8_t *)&_prefs.bot_commands_ch,   sizeof(_prefs.bot_commands_ch));
+    file.write((uint8_t *)&_prefs.bot_commands_room, sizeof(_prefs.bot_commands_room));
 
     // Tail sentinel — must be last. See NodePrefs::SCHEMA_SENTINEL. Its write is
     // the one we check: once the flash fills, writes return 0, so a good