fix(e2b): address the v7 review round

- restore the parent's AGENTS.md body around this branch's e2b row (the
  replay had resurrected the pre-profile-CLI layout, deleting the api/,
  bundle/, settings/, and credentials/ groups); the fs/lsp row
  condensations stay for the word budget
- aggregate the composite rollback failure, not the original error, when
  private state cleanup also fails — a surviving remote group is no
  longer hidden by a later cleanup error (triple-failure regression)
- own the state directory before the makeDir RPC, matching the terminal
  transaction, so a cancellation racing a committed creation still
  enters cleanup
- drop the hidden pollMs parameter defaults; the schemastery default is
  the one home, and tests pass the cadence explicitly
- restore spawn/spawnTerminal graceMs validation to the seam's
  documented bound (the earlier removal cited subprocess-local as not
  validating; it does), with rejection regressions

pnpm-lock.yaml

@@ -3190,6 +3190,9 @@ importers:
       '@deepseek-ai/dsh-subprocess':
         specifier: workspace:^
         version: link:../../subprocess/subprocess
+      '@deepseek-ai/dsh-timeout':
+        specifier: workspace:^
+        version: link:../../util/timeout
       cordis:
         specifier: ^4.0.0-rc.7
         version: link:../../../vendor/cordis