Zotero's three-pane layout (collections / items / detail) is fast because selecting an item doesn't reload the page. The current web UI reloads on every click to `/items/{id}`.
Proposal
Add a right-hand detail pane that updates in place when the user clicks an item row. Use htmx (single small `<script>` include) — no SPA framework.
Sketch
```html
...
Select an item to view details.
\`\`\`
- Server supports `?partial=1` on `/items/{id}` and returns just the `` fragment (no base.html wrap).
- `hx-push-url` keeps back-button behavior working.
- On small screens (<= 760px) fall back to the full-page detail route.
Acceptance
Zotero's three-pane layout (collections / items / detail) is fast because selecting an item doesn't reload the page. The current web UI reloads on every click to `/items/{id}`.
Proposal
Add a right-hand detail pane that updates in place when the user clicks an item row. Use htmx (single small `<script>` include) — no SPA framework.
Sketch
```html
...Acceptance