feat: focus priority, focus links, task list assignment, lists drag-and-drop, URL display fixes

- Focus page: turn sequence number into persistent editable priority (focus_priority column)
- Focus detail: add links section (add existing, create new, unlink) via focus_links junction table
- Focus detail: add copy and inline edit for checklist items
- Task detail lists tab: add existing list assignment and unlink actions
- Lists page: add drag-and-drop reorder support
- Links/bookmarks pages: remove artificial URL truncation, use CSS ellipsis

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

routers/lists.py

@@ -375,6 +375,19 @@ async def reorder_list(
     return RedirectResponse(url=request.headers.get("referer", "/lists"), status_code=303)
 
 
+@router.post("/reorder-all")
+async def reorder_all_lists(
+    request: Request,
+    item_ids: str = Form(...),
+    db: AsyncSession = Depends(get_db),
+):
+    repo = BaseRepository("lists", db)
+    ids = [i.strip() for i in item_ids.split(",") if i.strip()]
+    if ids:
+        await repo.reorder(ids)
+    return RedirectResponse(url=request.headers.get("referer", "/lists"), status_code=303)
+
+
 @router.post("/{list_id}/items/reorder")
 async def reorder_list_item(
     list_id: str,