fix(form-builder): explicit OrganisationScope bypass on every public-form query

Five models that the public form endpoints touch carry a global
OrganisationScope: FormSchema, Event, TimeSlot, FestivalSection,
PersonTag. The initial S2c implementation relied on the scope no-opping
because /public/forms/* has no `{organisation}` route parameter and
OrganisationScope::resolveOrganisationId returns null in that case.

That's accidentally-correct. Any middleware that sets an implicit org
context later (route model binding for platform admin, impersonation,
default-org fallback on an authed Sanctum session) would start
filtering public schema resolution by the wrong org.

- PublicFormTokenResolver: both FormSchema::query() calls now pass
  withoutGlobalScope(OrganisationScope::class). public_token is
  globally unique so this is safe.
- PublicFormController::timeSlots() / sections() / festivalEventIds():
  Event, TimeSlot, FestivalSection queries all explicit now, including
  the eager-loaded event relation on time-slots.
- PublicFormController::ownerEvent(): narrowed from
  Event::withoutGlobalScopes() to withoutGlobalScope(OrganisationScope)
  so future scopes (soft-delete, archived) aren't accidentally
  stripped.
- PublicFormSchemaResource::availableTagsByCategory: same narrowing on
  the PersonTag query.

PublicFormCrossOrgScopeTest pins the expectation — 4 cases hit every
public endpoint under a stashed foreign-org route parameter and assert
the owner-org data still surfaces. Verified the tests fail when the
fix is reverted (all 4 return `SCHEMA_NOT_FOUND` with the bypass
absent).

Full suite 893 → 897 green.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

api/app/Http/Resources/FormBuilder/PublicFormSchemaResource.php

@@ -8,6 +8,7 @@ use App\Enums\FormBuilder\FormFieldType;
 use App\Models\FormBuilder\FormField;
 use App\Models\FormBuilder\FormSchema;
 use App\Models\PersonTag;
+use App\Models\Scopes\OrganisationScope;
 use Illuminate\Http\Request;
 use Illuminate\Http\Resources\Json\JsonResource;
 
@@ -100,7 +101,10 @@ final class PublicFormSchemaResource extends JsonResource
             return [];
         }
 
-        $rows = PersonTag::withoutGlobalScopes()
+        // Named-scope bypass only — don't unintentionally strip future
+        // soft-delete or is_active scopes if any land later.
+        $rows = PersonTag::query()
+            ->withoutGlobalScope(OrganisationScope::class)
             ->where('organisation_id', $organisationId)
             ->where('is_active', true)
             ->orderBy('sort_order')