fix: move FEAT_RX_POWERSAVE to Features.h; no extra [LOC] on "Stop after" change

- FEAT_RX_POWERSAVE lived in MyMesh.h, but SettingsScreen.h only pulls
  Features.h -- it saw the flag only via include order, and an undefined
  macro in `#if` silently reads as 0, which would split the build the day
  it's flipped to 1. Now defined in Features.h (the home of FEAT_* flags),
  which MyMesh.h includes; comment/doc pointers updated.
- Changing Live Share's "Stop after" restarted the whole session, forcing
  an immediate re-announce [LOC] although the position hadn't changed. It
  now restarts only the duration clock (restartLocShareClock()).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

examples/companion_radio/Features.h

@@ -29,6 +29,23 @@
   #define FEAT_FULL_REFRESH_SETTING       0
 #endif
 
+// Hardware RX duty-cycle ("Pwr save") is disabled: the SX126x's duty-cycle
+// preamble detection needs the *actual transmitted* preamble to exactly match
+// what we're configured to expect (confirmed hardware behaviour, see SX1262
+// datasheet 6.1.3 and https://github.com/jgromes/RadioLib/issues/1597) --
+// something we can't guarantee across a mesh with mixed firmware. A mismatch
+// doesn't cost a little sensitivity, it silently drops every packet from that
+// sender regardless of signal strength (2026-09-22 field report: near-total
+// reception loss, unaffected by antenna). The real duty-cycle implementation
+// (RadioLibWrapper::armRecv()/CustomSX1262Wrapper::startPowerSaveRecv()) is
+// left in place for if a network-wide compatibility mechanism ever lands --
+// flipping this back to 1 requires solving that first, not just re-adding the
+// Settings toggle. See docs/development/roadmap.md for the full writeup.
+// Lives here (not MyMesh.h) so every `#if FEAT_RX_POWERSAVE` user sees the
+// same definition: an undefined macro in `#if` silently reads as 0, which
+// would split the build the day this is flipped to 1.
+#define FEAT_RX_POWERSAVE 0
+
 namespace Features {
 
 #if defined(EINK_DISPLAY_MODEL)

examples/companion_radio/MyMesh.cpp

@@ -288,7 +288,7 @@ bool MyMesh::getCADEnabled() const {
   // (unlike simple_repeater's CommonCLI `cad` command) — it's wired and
   // persisted for a future manual override, but always 0 today.
   // rx_powersave is never actually applied to the radio while FEAT_RX_POWERSAVE
-  // is 0 (see MyMesh.h) -- don't let a stale persisted byte from before that
+  // is 0 (see Features.h) -- don't let a stale persisted byte from before that
   // still auto-enable CAD here for a duty-cycle mode that isn't running.
 #if FEAT_RX_POWERSAVE
   return _prefs.cad_enabled || (_prefs.rx_powersave && !_prefs.client_repeat);
@@ -2001,7 +2001,7 @@ void MyMesh::begin(bool has_display) {
 #if FEAT_RX_POWERSAVE
   radio_driver.setPowerSaving(_prefs.rx_powersave && !_prefs.client_repeat);   // duty-cycle RX off while repeating (must hear all traffic)
 #else
-  radio_driver.setPowerSaving(false);   // see MyMesh.h FEAT_RX_POWERSAVE -- ignore any stale persisted rx_powersave byte
+  radio_driver.setPowerSaving(false);   // see Features.h FEAT_RX_POWERSAVE -- ignore any stale persisted rx_powersave byte
 #endif
   board.setLoRaFemLnaEnabled(_prefs.radio_fem_rxgain);
   board.setLoRaFemPaGainEnabled(_prefs.radio_fem_txgain);
@@ -2496,7 +2496,7 @@ void MyMesh::handleCmdFrame(size_t len) {
 #if FEAT_RX_POWERSAVE
       radio_driver.setPowerSaving(_prefs.rx_powersave && !_prefs.client_repeat);
 #else
-      radio_driver.setPowerSaving(false);   // see MyMesh.h FEAT_RX_POWERSAVE -- ignore any stale persisted rx_powersave byte
+      radio_driver.setPowerSaving(false);   // see Features.h FEAT_RX_POWERSAVE -- ignore any stale persisted rx_powersave byte
 #endif
       applyApc();   // pins power to the ceiling; apcActive() keeps it there while repeating
       MESH_DEBUG_PRINTLN("OK: CMD_SET_RADIO_PARAMS: f=%d, bw=%d, sf=%d, cr=%d", freq, bw, (uint32_t)sf,

examples/companion_radio/MyMesh.h

@@ -4,6 +4,7 @@
 #include <Mesh.h>
 #include "AbstractUITask.h"
 #include <helpers/ui/DisplayDriver.h>
+#include "Features.h"   // FEAT_RX_POWERSAVE, used by MyMesh.cpp
 
 // Forward declaration for UITask
 class UITask;
@@ -11,20 +12,6 @@ class UITask;
 /*------------ Frame Protocol --------------*/
 #define FIRMWARE_VER_CODE 13
 
-// Hardware RX duty-cycle ("Pwr save") is disabled: the SX126x's duty-cycle
-// preamble detection needs the *actual transmitted* preamble to exactly match
-// what we're configured to expect (confirmed hardware behaviour, see SX1262
-// datasheet 6.1.3 and https://github.com/jgromes/RadioLib/issues/1597) --
-// something we can't guarantee across a mesh with mixed firmware. A mismatch
-// doesn't cost a little sensitivity, it silently drops every packet from that
-// sender regardless of signal strength (2026-09-22 field report: near-total
-// reception loss, unaffected by antenna). The real duty-cycle implementation
-// (RadioLibWrapper::armRecv()/CustomSX1262Wrapper::startPowerSaveRecv()) is
-// left in place for if a network-wide compatibility mechanism ever lands --
-// flipping this back to 1 requires solving that first, not just re-adding the
-// Settings toggle. See docs/development/roadmap.md for the full writeup.
-#define FEAT_RX_POWERSAVE 0
-
 // Fallback only -- every real build (local or CI) goes through build.sh, which
 // always injects its own FIRMWARE_BUILD_DATE (today's date at build time).
 // __DATE__ is the compiler's own "Mmm dd yyyy" build-date macro, so a

examples/companion_radio/ui-new/LiveShareScreen.h

@@ -133,7 +133,7 @@ public:
         _dirty = true; break;
       case K_DURATION:
         _prefs->loc_share_duration_idx = (uint8_t)((_prefs->loc_share_duration_idx + (dir >= 0 ? 1 : NodePrefs::LOC_SHARE_DURATION_COUNT - 1)) % NodePrefs::LOC_SHARE_DURATION_COUNT);
-        _task->restartLocShareSession();   // a new length starts the session over
+        _task->restartLocShareClock();   // a new length starts the clock over (no extra [LOC] send)
         _dirty = true; break;
       case K_TARGET:
         if (enter) { _task->pickLocShareTarget(); return; }  // full chooser

examples/companion_radio/ui-new/UITask.cpp

@@ -3856,7 +3856,7 @@ void UITask::applyPowerSave() {
   // kept and restored when the repeater is switched off.
   radio_driver.setPowerSaving(_node_prefs->rx_powersave && !_node_prefs->client_repeat);
 #else
-  radio_driver.setPowerSaving(false);   // see MyMesh.h FEAT_RX_POWERSAVE -- ignore any stale persisted rx_powersave byte
+  radio_driver.setPowerSaving(false);   // see Features.h FEAT_RX_POWERSAVE -- ignore any stale persisted rx_powersave byte
 #endif
 }
 

examples/companion_radio/ui-new/UITask.h

@@ -340,6 +340,10 @@ public:
   void gotoLiveShareScreen();
   // Start the auto-share session clock afresh (next engine tick treats it as a new enable).
   void restartLocShareSession() { _loc_share_was_enabled = false; }
+  // Restart only the session's duration clock -- unlike restartLocShareSession(),
+  // no re-announce. For a changed "Stop after" length, where position hasn't
+  // changed. No-op before the engine has started a session (it sets the clock then).
+  void restartLocShareClock() { if (_loc_share_was_enabled) _loc_share_session_ms = millis(); }
   void gotoLocatorScreen();
   // Re-arm the locator state machine so the next evaluation initialises
   // silently (called by the Locator tool after the target/radius changes,