docs: enrich module docs with binary analysis cross-references

src/proto.rs

@@ -3,6 +3,11 @@
 //! This is a minimal, hand-rolled encoder. We do NOT use prost or any codegen
 //! because we need precise control over field ordering and encoding to produce
 //! byte-identical output to the captured webview traffic.
+//!
+//! The LS communicates with Google via gRPC over H2, using proto messages from
+//! the `exa.*_pb` package family. Init metadata (field 34 of the init request)
+//! carries the `detect_and_use_proxy` enum, model selection, and version info.
+//! See `docs/ls-binary-analysis.md` for the full proto schema reverse engineering.
 
 use crate::constants::{client_version, CLIENT_NAME};