Ported the alknet-http overlay verification to the channels-over-WS
session (tests/ws_overlay_ops.rs, test-support feature, 8 tests):
- overlay mechanism: browser-registered ops land in the connection's
Layer 2 overlay (register_imported), exposed via overlay_env() —
no PeerIds (browsers are not peers); PeerRef::Specific to a browser
id routes to nothing (NOT_FOUND)
- hub→browser call through compose_root_env's attached overlay
- AccessControl on browser ops gates hub calls (scope match allows,
missing scope FORBIDDEN)
- overlay dies with the connection; no leak between connections;
in-flight calls to browser ops resolve on close
- wire-level: 10 interleaved concurrent calls across two WS sessions
— no cross-correlation, no deadlock; disconnect mid-call resolves
and a fresh session works (no listener wedge)
byte_adapter: read_eof Notify now gated to the wss feature (its only
consumer is from_wss) so a test-support-only build is warning-free.
Verified: cargo test (182 lib), --all-features (227 lib + 5 MCP + 8
overlay + 10 WS integration), clippy -D warnings (default,
test-support, all-features), fmt.