Remove the page-access matrix: routes, controller methods, model

The last of the hand-rolled Access tabs. Its UI went in the previous commit; this
removes what sat behind it — the five settings/pages-access routes, the controller
methods serving them, the grant model, and the orphaned nav-visibility resolver that
read it. The table itself is dropped by a shell migration.

Nothing consulted any of it. Page access is a permission held through a group.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RDA3fQbsa3gaHCFoV1Q8Gg

src/Models/UnifiPageGrant.php

@@ -1,65 +0,0 @@
-<?php
-
-namespace Dashboard\Unifi\Models;
-
-use App\Models\NavItem;
-use App\Models\User;
-use Illuminate\Database\Eloquent\Model;
-use Illuminate\Database\Eloquent\Relations\BelongsTo;
-
-class UnifiPageGrant extends Model
-{
-    protected $table = 'unifi_page_grants';
-
-    protected $fillable = [
-        'nav_item_id',
-        'grantee_type',  // default | user | group | role
-        'grantee_id',    // null for grantee_type=default
-        'can_view',
-        'granted_by_user_id',
-    ];
-
-    protected $casts = [
-        'can_view' => 'boolean',
-    ];
-
-    public function navItem(): BelongsTo
-    {
-        return $this->belongsTo(NavItem::class);
-    }
-
-    public function grantedBy(): BelongsTo
-    {
-        return $this->belongsTo(User::class, 'granted_by_user_id');
-    }
-
-    /**
-     * Grant check with a per-page default fallback. Passes if the user
-     * matches an explicit user/group/role grant; otherwise falls back
-     * to the page's `default` row (deny by default — no row or
-     * can_view=false denies). Permission-based access is checked
-     * separately by the caller — grants extend, never revoke.
-     */
-    public static function userCanAccess(User $user, NavItem $navItem): bool
-    {
-        if ($user->is_super_admin) return true;
-
-        $groupIds = $user->groups()->pluck('groups.id');
-        $roleIds  = $user->roles()->pluck('roles.id');
-
-        $hasExplicit = static::where('nav_item_id', $navItem->id)
-            ->where('can_view', true)
-            ->where(function ($q) use ($user, $groupIds, $roleIds) {
-                $q->where(fn ($u) => $u->where('grantee_type', 'user')->where('grantee_id', $user->id))
-                  ->orWhere(fn ($g) => $g->where('grantee_type', 'group')->whereIn('grantee_id', $groupIds))
-                  ->orWhere(fn ($r) => $r->where('grantee_type', 'role')->whereIn('grantee_id', $roleIds));
-            })
-            ->exists();
-
-        if ($hasExplicit) return true;
-
-        return (bool) static::where('nav_item_id', $navItem->id)
-            ->where('grantee_type', 'default')
-            ->value('can_view');
-    }
-}