refactor: rename Personal Pro to Skipper and Team Pro to Admiral (#256)

Align paid tier names with Sencho's nautical identity. Internal variant
values ('personal'/'team') remain unchanged in code, database, and
Lemon Squeezy integration — only user-facing display names updated.

- Backend: requireTeamPro → requireAdmiral, TEAM_PRO_REQUIRED → ADMIRAL_REQUIRED
- Frontend: TeamProGate.tsx → AdmiralGate.tsx, TierBadge labels updated
- Website: PricingSection tier names and nautical descriptions
- Docs: all 11 affected pages renamed, nautical footnote added to licensing

docs/reference/settings.mdx

@@ -39,7 +39,7 @@ Manage your Sencho Pro license from this section.
 | **Trial status** | If on a trial, shows remaining days |
 | **Customer / Plan / Key** | Displayed when a Pro license is active |
 | **Renews** | Next renewal date for active subscriptions |
-| **Upgrade cards** | Dynamic plan cards with feature highlights and direct Lemon Squeezy checkout links. Community users see Personal Pro and Team Pro; Personal Pro users see Team Pro only |
+| **Upgrade cards** | Dynamic plan cards with feature highlights and direct Lemon Squeezy checkout links. Community users see Skipper and Admiral; Skipper users see Admiral only |
 | **Activate** | Enter a license key to activate Pro |
 | **Manage Subscription** | Opens the billing portal (active Pro only) |
 | **Deactivate License** | Reverts to Community features (active Pro only) |
@@ -196,8 +196,8 @@ Pro license holders get additional support channels:
 
 | Channel | Description |
 |---------|-------------|
-| **Email Support** | Direct email support (Personal Pro) |
-| **Priority Email Support** | Responses within 24 hours (Team Pro) |
+| **Email Support** | Direct email support (Skipper) |
+| **Priority Email Support** | Responses within 24 hours (Admiral) |
 
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