fix(chat): keep rectification sessions findable and keep the delivery card

Rectification answers now advance chat_sessions.updated_at (BUG-704).
A ?c= id missing from the loaded page is fetched before anyone may call
it deleted (BUG-705). The range card no longer has a post-card tie-break
button; live questions leave the card visible with adopt locked
(BUG-706/708). Spoken copy bans 相对支持度 (BUG-709).

Task docs assigned 700-704; qizheng already took 700-703.

frontend/tests/rectification-v9-migration.test.ts

@@ -1547,3 +1547,22 @@ test("host-fallback phase migration is forward-only and does not rewrite the fro
     /answer\.host_fallback/,
   );
 });
+
+test("rectification activity touches chat_sessions.updated_at without a metadata PATCH", () => {
+  const filename = "20260915010000_rectification_touch_chat_session.sql";
+  const touch = readFileSync(
+    new URL(`../supabase/migrations/${filename}`, import.meta.url),
+    "utf8",
+  );
+  assert.match(touch, /^begin;[\s\S]*^commit;$/m);
+  assert.equal(
+    existsSync(fileURLToPath(new URL(`../db/migrations/${filename}`, import.meta.url))),
+    false,
+    "business migration must not be copied into frontend/db/migrations (BUG-127/BUG-144)",
+  );
+  assert.match(touch, /rectification_touch_chat_session_requires_schema_owner/);
+  assert.match(touch, /touch_chat_session_from_rectification_case/);
+  assert.match(touch, /after update of last_activity_at/);
+  assert.match(touch, /session_type = 'birth_time_rectification'/);
+  assert.doesNotMatch(touch, /persistSession/);
+});