Merge master into codex/sandbox-policy-context

apps/web/tests/built-boot.snapshot.ts

@@ -111,6 +111,17 @@ it('boots the built plugin graph and renders a fixture session end to end', asyn
     expect(document.querySelector('[data-sample="bash-global"]')).not.toBeNull()
   }, { timeout: 10_000 })
 
+  // The write/edit turns render a real diff card through the assembled graph
+  // (the keyed FileMutationRow + DiffBlock), not just the fixture's raw text.
+  // The write turn's `hello fixture\n` proves the terminator rule end to end: a
+  // trailing newline terminates its line, so the footer reads `+1` (not a
+  // phantom `+2`) and one distinct file. The `+ ` prefix is a CSS ::before, so
+  // it is absent from textContent — assert on the line body and the footer.
+  const diffCards = [...document.querySelectorAll('[data-diff]')]
+  expect(diffCards.length).toBeGreaterThan(0)
+  const footers = diffCards.map(card => card.textContent ?? '')
+  expect(footers.some(text => text.includes('hello fixture') && text.includes('+1 -0 · 1 file'))).toBe(true)
+
   // The web render intent reaches the assembled boot graph: the fixture's
   // web_search / web_fetch turns render their keyed WebRow cards, proving the
   // registration, wire projection, and card rendering survive the real bundle