fix(nav): show the player game-data groups to staff

Staff are a superset of players (all player abilities plus their staff
tools), and the backend's player self-service surface is role-agnostic,
but MenuAccess.PLAYER gated "My characters/vendors/houses" on
role == player — so a signed-in admin/editor/moderator saw neither the
menu items nor, via the greyed personal streams, their own notification
options, even with linked characters.

Gate MenuAccess.PLAYER on isPlayer OR isStaff. The notifications screen
needs no change: once the backend returns the caller's linked accounts
(paired with RunicGateway/website), hasLinkedAccount resolves and the
personal streams enable themselves.

Tests: MenuAccessTest now asserts every staff role sees the player
game-data groups and a PLAYER entry, and an unrecognized role / anon
still cannot. Full unit suite passes.

Co-Authored-By: Claude <noreply@anthropic.com>

app/src/main/java/com/runicgateway/app/ui/navigation/Menu.kt

@@ -21,7 +21,12 @@ enum class MenuAccess {
     /** Visible to any signed-in account (§5, "My Account"). */
     SIGNED_IN,
 
-    /** Visible only to a player — the linked game-data groups (§6.3). */
+    /**
+     * The linked game-data groups (§6.3). Visible to any player **or** staff:
+     * staff are a superset of players (all player abilities plus their staff
+     * tools), and the backend's player self-service surface is role-agnostic, so
+     * a signed-in admin/editor/moderator sees + uses their own characters too.
+     */
     PLAYER,
 
     /** Visible to any staff role (admin/editor/moderator) — the M10 staff surface (§1). */
@@ -70,7 +75,7 @@ fun visibleEntries(entries: List<MenuEntry>, session: Session): List<MenuEntry>
         when (entry.access) {
             MenuAccess.PUBLIC -> true
             MenuAccess.SIGNED_IN -> session is Session.SignedIn
-            MenuAccess.PLAYER -> session is Session.SignedIn && session.user.isPlayer
+            MenuAccess.PLAYER -> session is Session.SignedIn && (session.user.isPlayer || session.user.isStaff)
             MenuAccess.STAFF -> session is Session.SignedIn && session.user.isStaff
             MenuAccess.MODERATOR -> session is Session.SignedIn && session.user.isModerator
         }