refactor: read verify_ssl from server.settings instead of server.client

Per Gemini review on PR homeassistant-ai#1128: server.client is a lazy @Property
(server.py) — accessing it for a single config bool would instantiate
the full HomeAssistantClient (httpx pool, settings re-read, log line)
on first access. server.settings is eager-initialized in the
HomeAssistantSmartMCPServer constructor and is the canonical source of
truth for verify_ssl.

Additional benefit: in OAuth deployment mode (__main__.py:868),
HomeAssistantSmartMCPServer is constructed with an OAuthProxyClient
whose __getattr__ proxies to a per-request OAuth client requiring an
authenticated request context. _restart_addon is a plain admin POST
without that context, so server.client.verify_ssl could have surfaced
as an auth error in OAuth mode. server.settings.verify_ssl sidesteps it
without depending on OAuthProxyClient's attribute-forwarding semantics.

Author: Patch76

src/ha_mcp/settings_ui.py

@@ -791,7 +791,7 @@ async def _restart_addon(_: Request) -> JSONResponse:
         # the connection will drop. A connection drop is actually success.
         try:
             async with httpx.AsyncClient(
-                timeout=5.0, verify=server.client.verify_ssl
+                timeout=5.0, verify=server.settings.verify_ssl
             ) as client:
                 resp = await client.post(
                     "http://supervisor/addons/self/restart",