- inteface Nette\Application\IRouter replaced by Nette\Routing\Router

Deleted CsrfProtection class, its tests, ProtectorId constant, and validation message.
The addProtection() method now only triggers a deprecation warning.

HTML forbids nested <form> tags, so a layout embedding a component that
renders its own <form> can't wrap its controls in another <form>. The
detached keyword emits an empty <form>...</form> at the opening position
and links every control back to it via the HTML5 form= attribute
(applied in Runtime::item()), so inputs submit correctly wherever they
sit in the DOM. Controls in nested containers and {form scope} inherit
the same link.

Unlike {form scope}/{formContext}, detached does render a <form>, so it
still accepts arguments, which apply to that tag.

Throws InvalidStateException when detached is used with a non-Form
Container or a form without an id.

The scope keyword before the form name makes {form} skip the <form>
tag while still pushing the form on the stack, so {input}/{label}/
{inputError} resolve against it. When nested inside another form, scope
resolves the name relatively to it (like {formContainer}); at the top
level it looks the name up in the registry. {formContext} keeps its
legacy behavior of always resolving from the registry.

Passing arguments to {form scope} or {formContext} now throws, since
neither renders a <form> tag to apply them to.

The {form name attr=val} syntax (no comma between the name and the
attributes) was tolerated. Trigger E_USER_DEPRECATED when a token
follows the name without a comma, pointing to the offending column.
The form still compiles — this only nudges users toward the canonical
{form name, attr=val} so future syntax extensions can use bare
keywords next to the name unambiguously.

- ChoiceControl, MultiChoiceControl: extracted getItem() method

Protection using Sec-Fetch and Origin headers is comprehensive, as they cannot be spoofed even if there is an XSS vulnerability on the server