🔨 Fix config.ini custom items, and 'all' (#24720)

buildroot/share/PlatformIO/scripts/configuration.py

                 elif not isdef:
                     break
                 linenum += 1
-            lines.insert(linenum, f"{prefix}#define {added} // Added by config.ini\n")
-            fullpath.write_text('\n'.join(lines), encoding='utf-8')
+            lines.insert(linenum, f"{prefix}#define {added:30} // Added by config.ini\n")
+            fullpath.write_text(''.join(lines), encoding='utf-8')
 
 # Fetch configuration files from GitHub given the path.
 # Return True if any files were fetched.
         iniok = False
         items = section_items(cp, 'config:base') + section_items(cp, 'config:root')
     else:
-        items = cp.items(sect)
+        items = section_items(cp, sect)
 
     for item in items:
         if iniok or not item[0].startswith('ini_'):
             fetch_example(ckey)
             ckey = 'base'
 
-        # Apply keyed sections after external files are done
-        apply_sections(cp, 'config:' + ckey)
+        elif ckey == 'all':
+            apply_sections(cp)
+
+        else:
+            # Apply keyed sections after external files are done
+            apply_sections(cp, 'config:' + ckey)
 
 if __name__ == "__main__":
     #