fix: small tauri websocket improvements

[peterchinman]

Fixes several edge cases in the Tauri WebSocket wrapper to better match native WebSocket behavior:

• Fire close after connection error: When a Tauri WebSocket connection fails, a close event is now emitted after the error event (code 1006). Native WebSockets always follow error with close, which the upper Websocket layer relies on to schedule reconnect retries.
• Fire close after send failure: If a .send() call rejects (e.g. the connection dropped mid-send), the socket now transitions to CLOSED and fires error + close events rather than silently failing.
• Set wasClean: true on normal close: The close event fired on a clean server-initiated close now correctly sets wasClean: true.
• Handle already-CLOSED socket in heartbeat: The heartbeat logic now also triggers cleanup when the underlying socket is in the CLOSED state (not just CLOSING), preventing stale connections from going undetected.

A comprehensive test suite for TauriWebSocketWrapper is also added.

Additionally does drive-by fixes on other things noticed in mobile sentry logs:

• unnecessary non-null assertion in layoutManager
• reduces the severity of a log from FloatingMenuContext.

[github-actions]

Preview: https://peter-small-tauri-websocket-im-hih2u8.preview.macro.com/app (f8cbf12)

[synoet]

restore / delete the changes to test