feat: switch text to UTF-8; add Unicode key events, dead keys & Czech layout; fix numpad navigation; add NumLock support

kernel/src/Drivers/PS2/Keyboard.hpp

@@ -63,4 +63,14 @@ namespace Drivers::PS2::Keyboard {
     // compute ASCII, since the lock is toggled centrally here.
     bool GetCapsLock();
 
+    // Current Num Lock state, owned here like Caps Lock. On (the default), the
+    // keypad types digits; off, it acts as the navigation keys printed on it.
+    bool GetNumLock();
+
+    // Set-1 scancodes of the keypad keys that are a digit/'.' with Num Lock on
+    // and Home/arrows/PgUp/End/PgDn/Ins/Del with it off (not '-' and '+').
+    inline bool IsKeypadNavScancode(uint8_t keycode) {
+        return keycode >= 0x47 && keycode <= 0x53 && keycode != 0x4A && keycode != 0x4E;
+    }
+
 };