M3 step 4: the LoRa Scanner App, Sniffer and Captures

The Sniffer lists packets newest first (time, RSSI, SNR, and for
Meshtastic the sender, receiver and hops), with the clear header and a
hex dump on Enter (Q96); `p` picks an EU868 preset, kept in Settings
(Q95). `c` starts a Capture: pcap with LoRaTap in /captures/lora, its own
Clean-up category, recorded by a small Service so it carries on with the
App closed (Q97, Q100). The Status Bar shows L while listening, bright on
each packet, and CAP while capturing (Q101). StorageService gains raw
appends for binary files. Debug Builds get `lora inject` to test all of
this with no transmitter in range: a Capture made on the device reads
back in TShark field for field.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

test/test_settings/test_settings.cpp

@@ -28,6 +28,8 @@ void test_defaults_when_store_is_empty() {
     TEST_ASSERT_TRUE(s.getBool(Setting::WifiEnabled));
     TEST_ASSERT_TRUE(s.getBool(Setting::GnssEnabled));     // Q58: on by default
     TEST_ASSERT_FALSE(s.getBool(Setting::CoordinatesDms));  // Q64: decimal degrees
+    TEST_ASSERT_EQUAL_INT32(0, s.getInt(Setting::LoraPreset));  // Q95: LongFast
+    TEST_ASSERT_FALSE(s.setInt(Setting::LoraPreset, 7));        // seven EU868 presets
     TEST_ASSERT_EQUAL_STRING("EU868", s.getString(Setting::Region).c_str());
     TEST_ASSERT_EQUAL_STRING("CET-1CEST,M3.5.0,M10.5.0/3", s.getString(Setting::Timezone).c_str());
 }