dlt_daemon_control_set_log_level_v2 never assigns req.apid/req.ctid; silently fails or crashes the daemon

## Summary

`dlt_daemon_control_set_log_level_v2` in `src/daemon/dlt_daemon_client.c`
does not actually parse the `apid` / `ctid` fields out of incoming
SET_LOG_LEVEL V2 control requests. As a result:

- A request with `apidlen == 0` and `ctidlen == 0` is silently no-op'd
(the function falls through to a path that calls
`dlt_daemon_context_find_v2` with NULL apid/ctid).
- A request with `apidlen != 0` causes a NULL pointer dereference at
line ~3723 and crashes the daemon.

The function is reachable from any client that can talk to the daemon's
control socket (dispatched from `dlt_daemon_handle_control_messages_v2`
at line 1273 of the same file).

## Evidence

The `DltServiceSetLogLevelV2` struct
(`include/dlt/dlt_common.h:760-769`) declares `apid` and `ctid` as
**pointers**, not inline arrays:

```c