Support bundle is now built on-the-fly when the user clicks the button,
regardless of whether other tasks are running:
- GET /export/support.tar.gz builds the bundle synchronously and streams it
directly to the client; the temp archive is removed after serving
- Remove POST /api/export/bundle and handleAPIExportBundle — the task-queue
approach meant the bundle could only be downloaded after navigating away
and back, and was blocked entirely while a long SAT test was running
- UI: single "Download Support Bundle" button; fetch+blob gives a loading
state ("Building...") while the server collects logs, then triggers the
browser download with the correct filename from Content-Disposition
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
