Merge remote-tracking branch 'origin/ntn-phy-test' into integration_2026_w12 (!3970)

Fix for NTN phy-test mode

- Corrected the initialisation of ntn params changed flag. Before this change on
  UE, Phy-test was not running in NTN mode.
- Removed the assert wrt slot > 64 to run FR2-NTN in phy-test
- SIB2, 19 required only in SA mode like SIB1
- Introduced new method to schedule a slot in UL/DL in Phy-test mode. Dmod/ Umod
  option in the command line with a value.
  - This ensures that the slot n (in slots per frame) will be scheduled if
    n % value == 0
  - For ex: --Dmod 1 means every slot will be scheduled
  - --Dmod 2 means every 2nd slot will be scheduled, like 0,2,4,6 until the
    slots per frame 1.
  - this can be used for testing FDD FR2 where slots go beyond 64 which is a
    limitation of -D/-U option.

executables/nr-ue.c

@@ -177,8 +177,6 @@ void init_nr_ue_vars(PHY_VARS_NR_UE *ue, uint8_t UE_id)
   ue->dci_thres   = 0;
   ue->target_Nid_cell = -1;
 
-  ue->nrUE_config.ntn_config.params_changed = false;
-
   // initialize all signal buffers
   init_nr_ue_signal(ue, nb_connected_gNB);