every control writes itself

The Save button is gone, and so is the SaveTarget context that announced it.
Every screen here is a preview of the thing being edited, so a change is already
visible before it is written — a button then asks somebody to confirm what they
can see.

useAutosave debounces a burst into one request. It takes the unsaved state as a
string rather than a flag, so a failed save is not retried on the next render,
and it flushes on unmount so a section change loses nothing.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

web/sections/PagesPanel.tsx

@@ -5,7 +5,7 @@ import { Input } from '@/components/ui/input';
 import { useClient } from 'hooks/useClient';
 import { readableError } from '../errors';
 import { useFlash } from '../useFlash';
-import { useSaveTarget } from '../SaveTarget';
+import { useAutosave } from '../useAutosave';
 import { usePages, type Page } from '../usePages';
 
 /**
@@ -143,7 +143,8 @@ export const PagesPanel = () => {
     }
   };
 
-  useSaveTarget(dirty, busy, save);
+  // The rows that differ, serialised — so one set of edits is attempted once. See useAutosave.
+  useAutosave(dirty ? JSON.stringify(changed()) : null, busy, save);
 
   const act = async (run: () => Promise<unknown>) => {
     setBusy(true);