* docs: update static/js/MODULE_SUMMARY.md to reflect current ES6 frontend
Rewrite the stale module summary to match the current no-build,
ES6-module frontend architecture. Adds coverage of app.js orchestration,
the chat/SSE pipeline (chat.js, chatStream.js, chatRenderer.js,
streamingRenderer.js), new subsystems (research/, compare/, document
streaming, cookbook*, skills.js), and removes the obsolete <script> load
order assumptions.
* cleanup: remove dead MEMORY_DOC / memory_doc paths (closes#4411)
Removes the unused MEMORY_DOC constant and the matching DataConfig
memory_doc field / set_data_paths entry. No runtime code imports or
references these paths, so this is a no-behavior-change dead-code
cleanup under the storage-architecture tracker #4377.