Initial commit: wireframe packet capture/analysis tool

Terminal packet capture and analysis tool built to learn the C++
memory model (byte layout, alignment, endianness, std::span over
unowned buffers) via a real capture pipeline.

- Hand-rolled L2-L4 decoders (Ethernet, IPv4, IPv6 with extension
  header walking, TCP, UDP) over std::span, no struct-casting
- L7 dissector interface with DNS, HTTP, and TLS SNI implementations
- pcapng read/write for Wireshark-compatible capture files
- Bounded capture queue: drop-on-backpressure for live capture,
  blocking push for faithful file replay
- Kernel-level BPF filtering (-f) and a separate display-only search
  (-g / interactive) that doesn't touch what's captured
- Replay mode (-r) reads a saved pcapng file back through the same
  pipeline as live capture, no root or live device needed
- pcap_stats() surfaces kernel/interface drops invisible to the
  capture queue's own counter
- Three frontends sharing one CaptureSession setup path: CLI, TUI
  (FTXUI, primary), GUI (Dear ImGui + SDL3, secondary)
- 89 unit tests (doctest) plus 9 libFuzzer harnesses covering every
  hand-rolled parser; fuzzing found and fixed a real OOM in the
  pcapng reader (unbounded allocation from an untrusted length field)

1 files changed, 26 insertions, 0 deletions

diff --git a/include/wireframe/search.hpp b/include/wireframe/search.hpp
new file mode 100644
index 0000000..4cb9203
--- /dev/null
+++ b/include/wireframe/search.hpp
@@ -0,0 +1,26 @@
+#pragma once
+
+#include <algorithm>
+#include <cctype>
+#include <string>
+
+// A display filter, distinct from -f's capture filter (wireframe/filter.hpp):
+// -f decides what's captured - and, combined with -w, what's written to
+// disk. This decides what's shown, without touching either. Same
+// distinction Wireshark draws between a capture filter and a display
+// filter, just without the display filter's expression language - a
+// plain case-insensitive substring match over the packet's summary line
+// is enough for "find the packets mentioning this host/port", which is
+// the actual use case.
+namespace wireframe {
+
+inline bool matches_search(const std::string& haystack, const std::string& needle) {
+    if (needle.empty()) return true;
+    auto it = std::search(haystack.begin(), haystack.end(), needle.begin(), needle.end(),
+                           [](unsigned char a, unsigned char b) {
+                               return std::tolower(a) == std::tolower(b);
+                           });
+    return it != haystack.end();
+}
+
+}  // namespace wireframe