Add token refresh and 401 retry for expired auth

[JeffSteinbok]

Fixes High #2 from code review: Token refresh / auth retry

Tokens were fetched once at login with no refresh mechanism. If the token expired during runtime, all REST API calls and WebSocket reconnections would fail silently until a full HA restart.

Changes

helpers.py

• Return actual HTTP status code on non-200 responses (was returning None for error codes)

pydreo/__init__.py

• _re_login() — Re-authenticates and updates the WebSocket transport token
• call_dreo_api() — Detects 401 responses and automatically retries once after re-login (login API itself is excluded to prevent infinite loops)

commandtransport.py

• update_token() — Allows the PyDreo manager to inject a refreshed token
• _start_websocket() — Restructured to rebuild the WebSocket URL on each reconnect attempt, picking up any token updates. Previously the URL was built once and reused for all reconnection attempts.

Tests

10 new tests:

• 401 retry with successful re-login
• No retry on login API itself (prevents infinite loop)
• No retry when re-login fails
• No retry on 200 (no false positives)
• _re_login updates transport token
• _re_login failure returns False
• _re_login skips transport update in debug mode
• update_token updates stored token
• WebSocket reconnect picks up fresh token
• URL format test updated for new loop structure