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

lib/lora/src/loratap.h

@@ -2,6 +2,7 @@
 
 #include <cstddef>
 #include <cstdint>
+#include <string>
 #include <vector>
 
 namespace roro::lora {
@@ -23,6 +24,9 @@ void appendPcapHeader(std::vector<uint8_t>& out);
 void appendRecord(std::vector<uint8_t>& out, uint32_t seconds, uint32_t micros, const RxInfo& rx, const uint8_t* data,
                   size_t len);
 
+// "/captures/lora/YYYYMMDD-HHMMSS.pcap" in UTC, dated like Tracks so Storage Clean-up can age it.
+std::string capturePath(int64_t utcSeconds);
+
 constexpr size_t kLoraTapSize = 15;
 constexpr size_t kRecordOverhead = 16 + kLoraTapSize;