Here is a conventional commit message summarizing the changes:
```
feat: Refactor SQL Explorer into blueprint
- Moved SQL Explorer routes (view explorer, save/load/execute/delete queries, view schema, plot queries) from `app.py` into a new blueprint at `routes/sql_explorer.py`.
- Added `/sql` URL prefix to the blueprint.
- Registered the new `sql_explorer_bp` blueprint in `app.py`.
- Removed the original SQL Explorer route definitions from `app.py`.
- Updated `url_for` calls in relevant templates (`sql_explorer.html`, `partials/sql_explorer/sql_query.html`, `base.html`) to reference the new blueprint endpoints (e.g., `sql_explorer.sql_explorer`).
- Updated `templates/changelog/changelog.html` to document this refactoring.
```
