android: the handoff — the pending rounds, the pipeline, and what is unverified

Everything written this session that has not been through the device: rounds 43
to 48 (each patch adversarially verified, 43's transient-notice expectation
fixed), a partial round 49, the pipeline scripts, the Android Auto design and
the icon comparison mock. Also the two harness changes that were never A/B'd —
adaptive waits, which may only shorten a declared wait and never lengthen it,
and a ship that runs the mock walk and the deploy at the same time. The A/B and
its 255-step baseline are in handoff/tools; main stays at what the phone has
actually walked.

handoff/rounds/ins-r26-doc-copy.txt

@@ -0,0 +1,5 @@
+record the queue holds; beside them, "Copy to a folder…" writes that same
+cached stream into a folder picked on this phone, as the plain file it is
+(`copy_stream_to_folder` — no re-download, no tagging, no library row; a
+track that has not finished streaming is counted back, never fetched).
+A moment after boot the phone warms the library's thumbnails the