Complete JavaScript integration Phase 4: Advanced Form Support

Implemented comprehensive form element access, manipulation, and submission control:

• Extended DOM system to create form elements during HTML parsing (INPUT, TEXTAREA, SELECT)
• Added JavaScript form properties: name, action, method, elements array access
• Implemented form.submit() and form.reset() methods with w3m form system integration
• Fixed DOM element creation timing issues for reliable getElementById functionality
• Added early JavaScript initialization during HTML parsing to ensure DOM availability
• Enhanced form submission control connecting JS API to w3m's _followForm mechanism
• Updated keybindings documentation with navigation commands (d, e, f, p)
• Added console.log JavaScript API for debugging support

All Phase 4 objectives completed and tested - form JavaScript integration fully functional.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

doc/MANUAL.html

@@ -958,6 +958,30 @@ Keybinding description for C-g had been moved as it did not fit to "Hyperlink op
 <td>M-m</td>
 <td>Pop up menu to navigate between hyperlinks</td>
 </tr>
+<tr>
+<td>NEXT_HEADING</td>
+<td>d</td>
+<td>d</td>
+<td>Move to the next heading</td>
+</tr>
+<tr>
+<td>PREV_HEADING</td>
+<td>e</td>
+<td>e</td>
+<td>Move to the previous heading</td>
+</tr>
+<tr>
+<td>NEXT_FORM</td>
+<td>f</td>
+<td>f</td>
+<td>Move to the next form element</td>
+</tr>
+<tr>
+<td>PREV_FORM</td>
+<td>p</td>
+<td>p</td>
+<td>Move to the previous form element</td>
+</tr>
 <!--  </table>-->
     <tr>
       <td colspan="4">