fix: add error403.blade.php to resolve crash on permission-gated pages

[Copilot]

Accessing any permission-gated page as a non-owner user crashed with View [error403] not found. The root cause: Template::display('errors.error403') resolves to errors::error403, finds the legacy .tpl.php, then loads the app layout with $module='errors'/$action='error403' — but the App view composer overrides $module with the current request's module (e.g. setting), causing @include("setting::error403") to fail.

Changes

• app/Domain/Errors/Templates/error403.blade.php — new Blade template for errors::error403

When a .blade.php file is present, Template::display() takes the blade code path: passes $layout directly to the view (not $module/$action), the template extends it, and the layout falls through to @yield('content') — entirely bypassing the App composer override.

@extends($layout)

@section('content')
<div class="errortitle">
    <h4 class="animate0 fadeInUp">{{ __('headlines.page_forbidden') }}</h4>
    <span class="animate1 bounceIn">4</span>
    <span class="animate2 bounceIn">0</span>
    <span class="animate3 bounceIn">3</span>
    ...
</div>
@endsection

Covers all affected controllers: Users, Projects, Clients, Settings, API, Timesheets, Calendar, Sprints, Tickets.

Original prompt

Bug: Accessing any permission-gated page as a non-owner user crashes with View [error403] not found.

Root cause: Multiple controllers call $this->tpl->display('errors.error403', responseCode: 403) but the Blade view file doesn't exist.

Fix needed:

1. Create app/Views/Templates/errors/error403.blade.php with a clean "403 Access Denied" page.
2. Use the existing error page layout/styling (check if there's an error404.blade.php or similar template to match).
3. The template should extend the app layout and display a simple "You don't have permission to access this page" message.

Files to reference:

• app/Domain/Setting/Controllers/EditCompanySettings.php line 50 — example of the errors.error403 call
• app/Domain/Errors/Controllers/Error403.php — the old controller-based error handler
• Look at existing error templates in app/Views/Templates/errors/ for the pattern

This affects all controllers that use the errors.error403 view: Users, Projects, Clients, Settings, API, Timesheets, etc.

Fixes #3323

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}