Add stubbed versions of _beam_ apis to vrtsim.

Allow arbitrary order of beam ids in set_beams2 function. This
allows the application to select any arbitrary order of beam ids.
The underlying transport mechanism still uses beam_map so the beam_ids
are ordered before sending.

Also replaced tx_beam_map/rx_beam_map into beam_map.

Also fixed an issue where --rfsimulator.enable_beams required an argument.

 - Added first beam optimization to combine_tx_buffers.
 - Added first beam & first peer optimization to rfsimulator_read_internal

This results in significant speed up for the first rx beam, first tx
beam and first peer which is the base case with beam simulation disabled.

In rfsim, received packets are dynamically allocated and freed when no longer
needed, which is dependent on the channel model, packet timestamp and packet
size (number of samples carried).

This commit fixes the packet age check for channels with nonzero channel offset
(most notalby NTN channels).

Also present:
 - extract the NTN satellite position update code to a separate function and
   call it once per trx_read call instead of once per rx beam.

Add a set of macros with designated initializers to simplify using
paramdef_t arrays in C++ source code. Fix clang error with
RFSIMULATOR_PARAMS_DESC using mixed designated and non-designated
initializers.

Added a new function for reading multiple beams concurrently.
The TX to RX beam combination is simplistic and based on beam gain.

- Received packets are dynamically allocated and kept in a
queue for as long as they are needed.

- The layout of the packets was changed from interleaved antennas
to non-interleaved antennas.

- Generate a contiguous buffer from saved packets as needed.

There is extra work caused by this change due to recv() call no
longer saving data directly into the circular buffer, however further
processing is easier due to contiguous nature of the tx antenna buffers
prepared. The impact on performance was not measured.

The simplifies some code in packet reception and is a prerequisite
for processing received without relying on circular buffer

A simplified beam switching simulation for rfsimulator. This works
mainly in 1 gNB - N UEs scenarios. This is not a real beamformer with
antenna, channel and propagation model. The way it works is that the
peers inform each other about the beams they transmit in, and on
reception before channel modelling, the beam data is combined based on
preconfigured rx_beam/tx_beam gain matrix.

Usage:
 - Add --rfsimulator.enable_beams to enable beam simulation
 - Add --rfsimulator.beam_gains <comma separated Toepliz form matrix of gains in dB>.

   Example list: 0,-5,-10

   Resulting matrix:

   [[0, -5, -10]
    [-5, 0, -5]]
    [-10, -5, 0]]

 - Add --telnetsrv if you want to control the beams manually. The command in telnet
   is "rfsimu setbeam <beam_map>", where beam_map is a uint64_t controling the
   reception beam and transmission beam. If the application is switching the beams
   automatically the beams will be overwritten as soon as the application chooses to
   switch beams.
Co-authored-by: Laurent Thomas <laurent.thomas@open-cells.com>

This function is to be called by the application to switch beams
on reception and transmission. When receiving new samples using
trx_read/trx_write the application is expected to be able to
determine which beam the samples belong to.

Co-authored-by: Laurent Thomas <laurent.thomas@open-cells.com>

Convert rfsimulator C source code to C++ to access to STL.

Integration `2025.w50`

* !3638 NR UE: calculate TA based on SIB19 information in NTN mode, if autonomous TA is not enabled
* !3624 NR UE: improve handling of Handover procedures
* !3807 doc: Update doc for IF setup
* !3741 Update documenation for handover
* !3798 Fix for computation of PRACH occasions and association period
* !3808 Add symbol timing functions for NR_DL_FRAME_PARMS + optimization for slot timing counterparts

Closes #981

See merge request oai/openairinterface5g!3806

Add symbol timing functions for NR_DL_FRAME_PARMS + optimization for slot timing
counterparts

Add two new functions for calculation symbol timestamp and symbol duration for
NR_DL_FRAME_PARMS. Also includes an optimization focused on removing
inefficiencies related slot-related counterparts.

For 15kHz SCS, symbols with index 0 and 7 have longer cyclic prefix.
This is now fixed in frame parms struct.

1. Removed function pointers for functions get_samples_per_slot(),
   get_samples_slot_timestamp() and get_slot_from_timestamp() as it does
   not offer any advantage. The functions are now called directly from
   everywhere.
2. Optimized these functions by removing loops where ever possible.

Fix for computation of PRACH occasions and association period

Update documenation for handover

Update documentation for handover to include the changes that were made after
upgrading the CI handover setup (attenuator, USRPs synchronization)

doc: Update doc for IF setup

Update IF setup doc, clarify how to set if_freq with large value in the gNB
configuration file. Per the libconfig manual, 64-bit integers are represented
like regular integers but require an appended "L"
(https://www.hyperrealm.com/libconfig/libconfig_manual.html#g_t64_002dbit-Integer-Values).

Update documenation for F1 handover to include the changes that were made after upgarding the CI handover setup (attenuator, USRPs synchronization)

NR UE: calculate TA based on SIB19 information in NTN mode, if autonomous TA is not enabled

To achieve the goal, the hyper frame number (HFN) is introduced at the NR UE
PHY, MAC and RRC layers.

Besides this, we also implemented an orbit propagation to improve the accuracy
of N_UE_TA_adj, and a fix to keep the N_TA from RAR and MAC CE.

Fixes #981

Integration `2025.w49`/`v2.4`

* !3786 Consistently use OAI_RNGSEED env variable for RNG
* !3758 Add yq to edit yaml files and add yaml-dev library in containers missing it
* Fix RFemulator noise device RNG initialization
* !3780 NGAP: fix PDU Session Release Response
* !3795 Increase Aerial-based L2 test core number
* !3794 Fix missing E2SM-RC message forward
* !3660 Fixes for BWP switching
* !3797 Fix FAPI WLS timing, UL counter, doc
* release notes v2.4

See merge request oai/openairinterface5g!3792

Add two new functions for calculation symbol timestamp and symbol
duration for NR_DL_FRAME_PARMS. These functions are not using
the existing indirection mechanism via function pointers as this
prevents the compiler from properly optimizing the code.

Merge remote-tracking branch 'origin/fapi-wls-fixes-timing-counter-doc' into integration_2025_w49 (!3797)

Fix FAPI WLS timing, UL counter, doc

- Fix FAPI WLS timing
- Fix periodical PNF UL throughput logs
- Update documentation to better explain how to run WLS with radio (USRP
  B210)

Fixes for BWP switching

This MR fixes some issues when performing BWP switching via
reconfiguration. It also adds a CI test for BWP switching.  # Please
enter a commit message to explain why this merge is necessary,

In all cases (CFRA in SA for HO, or CFRA in NSA/do-ra for access), the
UE has the full configuration already. We can therefore directly switch
to a dedicated search space, as it is already known to the UE.

Trigger various BWP switches through telnet, and test traffic after each
switch.