Inject route parameters as controller method arguments

[philipobenito]

Allow route parameters to be injected directly as controller method arguments rather than requiring the $args array.

Current behaviour:

$router->map('GET', '/users/{id}', function (ServerRequestInterface $request, array $args) {
    $id = $args['id'];
});

Proposed behaviour (via strategy or opt-in):

$router->map('GET', '/users/{id}', function (ServerRequestInterface $request, string $id) {
    // $id injected directly
});

Considerations:

• Requires reflection to inspect controller signatures, which has performance overhead
• The ServerRequestInterface injection should remain optional
• Should be implemented as a strategy concern, not in the routing core
• Edge cases around parameter naming mismatches, default values, and variadic parameters
• Could be a companion package rather than core feature

Target: 7.x