Add two-factor authentication fields to pp_users table and update .htaccess for security

- Added columns for two-factor authentication (2FA) in the pp_users table:
  - twofa_enabled (TINYINT)
  - twofa_email (VARCHAR)
  - twofa_code_hash (VARCHAR)
  - twofa_expires_at (DATETIME)
  - twofa_sent_at (DATETIME)
  - twofa_failed_attempts (INT)
- Updated the twofa_enabled and twofa_email for user with id 0.
- Enhanced .htaccess to disable directory listing, block execution of sensitive files, and prevent serving hidden files.

admin/templates/site/unlogged-layout.php

@@ -63,9 +63,15 @@
                       </div>
                     </div>
                   </div>
-                   <div class="sumbit">
-                      <button class="btn">Zaloguj się</button>
-              </div>
+                  <div class="form-group">
+                    <div class="col col-sm-12" style="align-items: center; display: flex;">
+                      <input id="remember" type="checkbox" name="remember" value="1">
+                      <label class="remember" style="margin-bottom: 0; margin-left: 5px;"> Pamiętaj mnie 14 dni</label>
+                    </div>
+                  </div>
+                  <div class="sumbit">
+                    <button class="btn">Zaloguj się</button>
+                  </div>
                 </form>
                 <div class="copyright">
                  <a href="https://www.project-pro.pl/"> &copy; <?= date( 'Y' );?> Project-Pro</a>