bug(router): RouterUri::addMiddleware() silently ignores class references

[usernane]

Bug Description

RouterUri::addMiddleware() accepts a string parameter and resolves it by registered middleware name or group name. When a developer passes a class reference (e.g., StartSessionMiddleware::class), the method silently does nothing — no error, no warning. The middleware is simply not applied to the route.

This is particularly problematic because:

• Using ::class is the natural, type-safe PHP pattern
• The RouteOption::MIDDLEWARE option accepts strings, so passing a class constant looks correct
• The failure is completely silent, making it very hard to diagnose

Steps to Reproduce

1. Register a route with middleware using the class reference:

Router::api([
    RouteOption::PATH => 'apis/example',
    RouteOption::TO => SomeService::class,
    RouteOption::MIDDLEWARE => StartSessionMiddleware::class,
]);

2. Make a request to the route
3. The session middleware is never executed

Expected Behavior

Either:

1. The middleware should be resolved by class name (instantiate and register if needed), or
2. An exception should be thrown indicating the middleware was not found

Actual Behavior

The middleware string "WebFiori\Framework\Middleware\StartSessionMiddleware" doesn't match the registered name 'start-session' nor any group name. The method returns silently without adding any middleware to the route.

Relevant code in RouterUri.php:

public function addMiddleware(string $name) {
    $mw = MiddlewareManager::getMiddleware($name);

    if ($mw === null) {
        $group = MiddlewareManager::getGroup($name);

        foreach ($group as $mw) {
            $this->assignedMiddlewareList[] = $mw;
        }

        return; // Silent return — no middleware added, no error
    }
    $this->assignedMiddlewareList[] = $mw;
}

WebFiori Version

3.0.0-RC1

PHP Version

8.4.18

Operating System

Linux

Additional Context

Proposed fix — support class resolution and throw on invalid values:

public function addMiddleware(string $name) {
    $mw = MiddlewareManager::getMiddleware($name);

    if ($mw === null) {
        $group = MiddlewareManager::getGroup($name);

        if (!empty($group)) {
            foreach ($group as $mw) {
                $this->assignedMiddlewareList[] = $mw;
            }
            return;
        }

        // Try resolving as class name
        if (class_exists($name) && is_subclass_of($name, AbstractMiddleware::class)) {
            $inst = new $name();
            MiddlewareManager::register($inst);
            $this->assignedMiddlewareList[] = $inst;
            return;
        }

        throw new \InvalidArgumentException(
            "Middleware '$name' is not registered, does not match any group, "
            . "and is not a valid middleware class."
        );
    }
    $this->assignedMiddlewareList[] = $mw;
}

This supports both patterns (name string and class reference), and fails loudly on typos or invalid values instead of silently ignoring them.