[fix](trx-rs): add FT2 raw-window candidate search

Use an FT2-specific raw sample window and candidate acquisition path.
Keep the build clean by removing the stale monitor warning.

Co-authored-by: OpenAI Codex <codex@openai.com>
Signed-off-by: Stanislaw Grams <stanislawgrams@gmail.com>

external/ft8_lib/common/monitor.c

@@ -197,8 +197,6 @@ void monitor_resynth(const monitor_t* me, const ftx_candidate_t* candidate, floa
     const int num_ifft = me->nifft;
     const int num_shift = num_ifft / 2;
     const int taper_width = 4;
-    const int num_tones = 8;
-
     // Starting offset is 3 subblocks due to analysis buffer loading
     int offset = 1;                          // candidate->time_offset;
     offset = (offset * me->wf.time_osr) + 1; // + candidate->time_sub;