Merge branch 'master' into t3code/add-traffic-test-modes

feat: streamer/video/burst/download traffic modes with display smoothing

fix: working stop button, staged submit flow with upload test

feat: single/multi modes, 100GB steady-state test with origin pooling

feat: single-phase sweep with UUIDv7 cache-busting

feat: worker-based ranged downloads with connection auto-tune

feat: download speed meter with parallel chunk testing

feet: Accept POST request

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