After broadcasting a group message, wait 5s to see if any neighbor
repeated the flood and use the outcome to mark the on-device entry
and the BLE-app mirror.
- ContentionTracker gets extractDupeCount(hash): finds the tracked
entry, captures dupe_count, finalizes (folds into EMA, marks
inactive), returns the count or -1.
- BaseChatMesh::sendGroupMessage gains an optional out_hash param;
when set, the FNV-1a packet hash is also pre-registered with the
contention tracker so heard retransmits get counted (originated
floods weren't tracked before, only relays).
- Mesh::getContentionTracker() promoted to public so the UI can
query after the feedback window.
JoystickUITask grows a 4-slot pending-channel table with per-slot
k_timer (5s one-shot). startPendingChannel() broadcasts, adds the
local _ch_previews entry with path_len = OUT_PATH_SENT, and starts
the feedback timer. The timer ISR sets a feedback_due flag; the
loop's processPendingChannelFeedback() picks it up, calls
extractDupeCount(), and rewrites the preview's path_len to
OUT_PATH_SENT_HEARD (0xFD) or OUT_PATH_SENT_UNHEARD (0xFC) — which
formatHopCount renders as "sent+" / "sent?".
The deferred BLE-app mirror queues only on outcome with body prefix
"(>>✓) " (heard) or "(>>✗) " (not heard). queueLocalSentChannelMessage
gains a heard_repeat parameter for the selection.
Both channel send entry points (sendComposedMessage's channel branch
and sendChannelMessage) now route through startPendingChannel().
liquidraver