feat(sim): board feature parity (reset/GPS/sensors/admin/keyboard) + input fixes

Rounds out the browser sim harness with the rest of the physical board's
interactions: a reset button (JS-driven, since board.reboot() is inert
under -sEXIT_RUNTIME=0), GPS input wired into a real LocationProvider via
new SimSensorManager, JS-settable battery/environment telemetry, an
admin/repeater-login test hook (sendRoomLogin against the default
"password"), and full physical-keyboard text entry (printable ASCII
passthrough into the existing KeyboardWidget, Tab->KEY_KB_ENTER submit).

Also fixes three real bugs found while exercising all of this in a real
browser:
- UITask.cpp's native-only stdin poll branch had no __EMSCRIPTEN__
  exclusion, so it also compiled into the wasm build and called a real,
  blocking window.prompt() on nearly every frame -- the actual cause of
  the reported time/controls jumping. Now gated to native only.
- 'n'/'p' were mapped as Next/Prev keyboard shortcuts, colliding with
  typing those literal letters. Removed the shortcuts; added explicit
  Next/Prev buttons to mesh.html (previously relied solely on them).
- Buttons grabbed native browser keyboard focus on click, so a later
  stray Enter/Space could silently re-trigger a previously-clicked button
  (e.g. Reset). mousedown now calls preventDefault() on all buttons.

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

examples/companion_radio/main.cpp

@@ -422,4 +422,54 @@ extern "C" EMSCRIPTEN_KEEPALIVE int sim_test_open_dm_with_first_contact() {
   return 1;
 }
 #endif
+
+// Same idea as findFirstChatContact() above, but for the first known
+// admin-loginable contact (a repeater or room server) instead of another
+// chat instance.
+static bool findFirstAdminContact(ContactInfo& out) {
+  int n = the_mesh.getNumContacts();
+  for (int i = 0; i < n; i++) {
+    ContactInfo ci;
+    if (the_mesh.getContactByIdx(MAX_ANON_CONTACTS + i, ci) &&
+        (ci.type == ADV_TYPE_REPEATER || ci.type == ADV_TYPE_ROOM)) {
+      out = ci;
+      return true;
+    }
+  }
+  return false;
+}
+
+#ifdef DISPLAY_CLASS
+// Jumps the on-device UI straight to AdminScreen for the first known
+// repeater/room contact -- UITask::openAdminFor(ci, false), the exact same
+// function NearbyScreen's "Nodes" Hold-Enter admin action calls (see
+// NearbyScreen.h:709), so a test harness can screenshot the real Admin
+// screen instead of scripting contact-list navigation key-by-key. Returns
+// 1 if a repeater/room contact was found and the screen switched, 0 if not.
+extern "C" EMSCRIPTEN_KEEPALIVE int sim_test_open_admin_with_first_repeater() {
+  if (!g_sim_ready) return 0;
+  ContactInfo ci;
+  if (!findFirstAdminContact(ci)) return 0;
+  ui_task.openAdminFor(ci, false);
+  return 1;
+}
+#endif
+
+// Submits a login against the first known repeater/room contact via
+// MyMesh::sendRoomLogin() -- the exact same function AdminScreen's own
+// submit button calls (examples/companion_radio/ui-new/AdminScreen.h) --
+// so a test harness can verify the admin/password flow without scripting
+// the on-device virtual keyboard. Only reports whether the login *request*
+// was sent (matching sim_test_send_msg_to_first_contact()'s same
+// synchronous-only contract) -- the actual accept/reject arrives async via
+// AbstractUITask::onRoomLoginResult() and is visible on AdminScreen once
+// sim_test_open_admin_with_first_repeater() has switched to it. Returns 1
+// if sent, 0 if send failed, -1 if no repeater/room contact known yet.
+extern "C" EMSCRIPTEN_KEEPALIVE int sim_test_login_first_repeater(const char* password) {
+  if (!g_sim_ready) return -1;
+  ContactInfo ci;
+  if (!findFirstAdminContact(ci)) return -1;
+  uint32_t est_timeout;
+  return the_mesh.sendRoomLogin(ci, password, est_timeout) ? 1 : 0;
+}
 #endif

examples/companion_radio/ui-new/UITask.cpp

@@ -2424,7 +2424,21 @@ void UITask::loop() {
   } else if (ev == BUTTON_EVENT_TRIPLE_CLICK) {
     if (!_locked) enqueueKey(handleTripleClick(KEY_SELECT));
   }
-#elif defined(SIM_PLATFORM)
+#elif defined(SIM_PLATFORM) && !defined(__EMSCRIPTEN__)
+  // Native terminal input ONLY -- this branch previously had no
+  // __EMSCRIPTEN__ exclusion, so it also compiled into the wasm build
+  // (SIM_PLATFORM is defined there too, and UI_HAS_JOYSTICK/PIN_USER_BTN
+  // are both unset for variants/sim). Every tick it called real select()/
+  // read() on fd 0; under Emscripten, with no stdin ever wired up, that
+  // hits the runtime's default TTY device, which falls back to a real,
+  // blocking window.prompt("Input: ") -- so every single browser tab
+  // running the wasm build was popping a native dialog on nearly every
+  // frame, discovered by seeing Playwright's page 'dialog' event fire
+  // continuously from the moment the module boots. The wasm build's own
+  // input already comes through sim_enqueue_key()/injectSimKey() (see
+  // above, in the #if defined(SIM_PLATFORM) && defined(__EMSCRIPTEN__)
+  // block) -- this stdin-poll branch was only ever meant for Phase 1's
+  // native terminal target.
   // Native terminal input: stdin is put into raw/non-canonical mode by
   // variants/sim/sim_main.cpp's main(), so keys arrive here one at a time
   // with no Enter-to-submit line buffering. Non-blocking select() on fd 0