Restore select2 input functionality after Bootstrap 5 cleanup

- Restored select2 input type from earlier commit d4adf5e^
- Added select2 import to bootstrap5-editable.js bundle
- Updated demo with select2 example (requires select2 library)
- Enhanced README.md with comprehensive select2 documentation
- Includes support for static sources, AJAX sources, and advanced configuration
- Select2 library must be included separately (not bundled)

demo/demo.js

@@ -70,4 +70,30 @@ $(function() {
         }
     });
 
+    // Note: This would require select2 library to be loaded
+    // $('#select2-test').editable({
+    //     type: 'select2',
+    //     url: 'demo/demo.php',
+    //     source: [
+    //         {id: 'us', text: 'United States'},
+    //         {id: 'gb', text: 'Great Britain'},
+    //         {id: 'ru', text: 'Russia'},
+    //         {id: 'de', text: 'Germany'},
+    //         {id: 'fr', text: 'France'},
+    //         {id: 'es', text: 'Spain'},
+    //         {id: 'it', text: 'Italy'}
+    //     ],
+    //     value: 'us',
+    //     select2: {
+    //         placeholder: 'Select Country',
+    //         allowClear: true
+    //     },
+    //     success: function(response, newValue) {
+    //         console.log('Select2 success:', newValue);
+    //     },
+    //     error: function(response) {
+    //         console.log('Select2 error:', response);
+    //     }
+    // });
+
 })

demo/index.html

@@ -63,6 +63,22 @@
                 </a>
             </div>
 
+            <div class="container">
+                <h3>Test X-Editable Select2</h3>
+                <p>Click to select from a larger list with search (Note: Requires select2 library):</p>
+
+                <a
+                    href="#"
+                    id="select2-test"
+                    class="editable editable-click"
+                    data-type="select2"
+                    data-pk="104"
+                    data-title="Select Country"
+                >
+                    Click to select country
+                </a>
+            </div>
+
         </form>
     </body>
 </html>