fix(auth): align console login handoff and guest plan CTAs

[Blankll]

What

Aligns the SqlKit client with the console handoff behavior shipped for DocKit (wentsen/geekfun#64):

1. authService always opens the production console at https://console.geekfun.club:
   • the dev-only localhost:5174 branch is removed;
   • the retired console-geekfun.wentsen.com host (legacy Aliyun hosting, scheduled for removal) is no longer used — its page cannot pass Cloudflare Turnstile because the widget's sitekey is bound to console.geekfun.club.
2. Settings → "Account & Plan" no longer shows inapplicable actions when signed out:
   • Refresh entitlements is hidden for guests (the Rust command returns "not logged in" without any network call);
   • the misleading "Could not verify entitlements — check your network and refresh" line is suppressed for guests;
   • the plan refresh on mount only runs for a logged-in session;
   • guests now get [Upgrade] + [Start free], where Start free opens the console register page with ?source=sqlkit.

Test plan

• Signed out → Settings → plan card shows Upgrade + Start free (no Refresh, no "could not verify" line); Start free opens console.geekfun.club/register?source=sqlkit and the Turnstile widget renders normally.
• "Login" link opens console.geekfun.club/login?source=sqlkit.
• Signed in (Community) → Refresh + Upgrade + Logout unchanged.

The console side (handling source=sqlkit) ships in wentsen/geekfun#64.