fix(homecore-api): close WS auth bypass + reply-theater, harden dev bin (ADR-161 A1/A2/A8)

A1 (CRITICAL): the /api/websocket handshake accepted any non-empty token,
ignoring the LongLivedTokenStore whitelist the REST path enforces — a full
WS auth bypass. Now validates via state.tokens().is_valid() before auth_ok;
wrong tokens get auth_invalid + close.

A2 (HIGH): WS command replies were pushed into an mpsc whose only consumer
logged and discarded them — no result/pong/event reached the client. Split
the socket with futures StreamExt::split; a dedicated writer task drains the
response channel onto the wire.

A8 (HIGH): the homecore-api dev bin bound 0.0.0.0 with unconditional
allow-any auth and no env path. Wired the HOMECORE_TOKENS env path (dev
fallback warn-logged when unset) and defaulted the bind to 127.0.0.1
(HOMECORE_BIND to opt into LAN).

Tests (fail on old source):
- ws_handshake::wrong_token_is_rejected (old → auth_ok)
- ws_handshake::result_reply_is_received / ping_pong_reply_is_received (old → timeout)
- server_bin_auth::provisioned_bin_rejects_wrong_bearer / from_env_path_enforces_whitelist

Co-Authored-By: claude-flow <ruv@ruv.net>

v2/crates/homecore-api/Cargo.toml

@@ -33,8 +33,12 @@ chrono = { version = "0.4", features = ["serde"] }
 
 uuid = { version = "1", features = ["v4", "serde"] }
 dashmap = "6"
+futures-util = { version = "0.3", default-features = false, features = ["sink"] }
 
 [dev-dependencies]
 tower = { version = "0.5", features = ["util"] }
 hyper = "1"
 http-body-util = "0.1"
+# End-to-end WS handshake + reply tests (HC-WS-01/02, ADR-161).
+tokio-tungstenite = "0.24"
+futures-util = { version = "0.3", default-features = false }