fix(repeater): close radio-profile bypass paths, dedupe preset/BW logic

CMD_SET_RADIO_PARAMS and the on-device Settings radio editors
(Freq/SF/BW/CR/Preset) called radio_driver.setParams() directly instead
of applyRepeaterRadio(), so editing the companion's own radio params
while relaying on a dedicated profile silently retuned the live radio
off that profile. Both now route through applyRepeaterRadio(), the
single decision point already used at boot and by the on-device
repeater toggle.

Also: overhear-suppression matched queued packets by payload hash
alone, so it could cancel a queued direct-route retransmit that
happened to share a hash with an overheard flood packet — now scoped
to flood-queued entries only. repeaterProfileValid()'s frequency floor
(100 MHz) is raised to 150 MHz to match the radio's actual validated
range. RepeaterScreen's preset-name lookup now uses the same
epsilon-tolerant float comparison as Settings instead of exact ==,
avoiding inconsistent "Custom" labeling between the two screens.

Dedupe: the BW-options table, the value-column x-offset math, and the
default-profile-seeding block had each drifted into two or three
independent copies (RepeaterScreen vs Settings, MyMesh constructor vs
DataStore.cpp upgrade path); factored into shared helpers in
RadioPresets.h / NodePrefs.h.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

examples/companion_radio/RadioPresets.h

@@ -1,4 +1,5 @@
 #pragma once
+#include <math.h>
 
 // Community-suggested per-region RF presets (freq/bw/sf/cr), sourced from the
 // MeshCore app's "suggested_radio_settings" config plus a few community additions.
@@ -33,3 +34,17 @@ static const RadioPreset RADIO_PRESETS[] = {
   { "Vietnam (Narrow)",        920.250f,  62.5f,  8, 5 },
 };
 static const int RADIO_PRESET_COUNT = sizeof(RADIO_PRESETS) / sizeof(RADIO_PRESETS[0]);
+
+// Standard SX126x/SX127x LoRa bandwidths (kHz) — manual BW fields (companion and
+// repeater profile alike) cycle through these rather than a free-form value, so
+// they can't land on an unsupported setting.
+static const float LORA_BW_OPTS[] = { 7.8f, 10.4f, 15.6f, 20.8f, 31.25f, 41.7f, 62.5f, 125.0f, 250.0f, 500.0f };
+static const int LORA_BW_OPT_COUNT = sizeof(LORA_BW_OPTS) / sizeof(LORA_BW_OPTS[0]);
+
+// True if (freq, bw, sf, cr) matches the radio's currently-applied (cur_*) params.
+// Floats are compared with a small epsilon since they may have round-tripped
+// through unit conversions (e.g. kHz integers from the companion app).
+static inline bool radioParamsMatchPreset(float cur_freq, float cur_bw, uint8_t cur_sf, uint8_t cur_cr,
+                                           float freq, float bw, uint8_t sf, uint8_t cr) {
+  return fabsf(cur_freq - freq) < 0.001f && fabsf(cur_bw - bw) < 0.001f && cur_sf == sf && cur_cr == cr;
+}