Driver: launch, input sends, and quit are still unbounded

[leoafarias]

pollFrameAdvance, waitForText, waitFor, and waitForAbsent now spend one
budget across their requests, so a stalled app cannot hold them past their
timeout. Three paths in package:noir_driver are still unbounded.

• The input request itself. sendBytes awaits the ext.noir.driver.* RPC
  with no deadline. The settle window that follows it is bounded, but the send
  is not, so a driven app that stops answering blocks before the bounded part
  begins.
• NoirDriver.launch. Process start and VM-service attach have no ceiling
  of their own. awaitDriverReady is bounded, but only once it is reached.
• quit and kill. Both await the process exit code. An app whose cleanup
  hangs leaves the caller waiting with no timeout.

A test process that hangs in any of these is a hung suite rather than a failing
one, which is the outcome the wait budgets exist to avoid.

Suggested shape: extend the existing PollDeadline in
packages/noir_driver/lib/src/driver_polling.dart to cover a single request,
and give launch and quit explicit, documented ceilings. Decide separately
whether a launch timeout should kill the process it started.