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/commit-msg26.txt

@@ -0,0 +1,14 @@
+android: a streamed file copied into a folder, the listening port, the dev build's diagnostics
+
+The now-playing sheet's streamed track can be copied into a folder picked
+on the phone, as the file it is — the cache written out, nothing downloaded
+again, no library row (copy_stream_to_folder, which the desktop has had a
+command for and no UI). You → Sharing carries the listening port, what
+peers dial when they download from you: unset is the client's own 50300,
+the app asks the router to forward it over UPnP and falls back to the
+server relaying, and a change applies on the next connect. The dev flavour
+gets the desktop's debug overlay as a screen under This phone — CPU,
+memory, the network, the stream and its loudness, what the pre-buffer is
+fetching, the size of the play history — behind devBuild in util.js, which
+is Vite's own DEV flag, so the embedded build the phone keeps has no row
+to tap.