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-msg32.txt

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+android: the boot chain goes out in one round, and a census that holds it there
+
+Thirty rounds of onMount had never been read end to end, and read end to end
+it was a queue: two dozen commands with a critical path ten deep, because
+Tauri's `listen` is an invoke like any other. loadLibrary asked for five
+independent SQLite reads one behind the other, bindSlsk registered eight
+listeners one behind the other, and watchLibrary and the player's bindEvents
+did two each. None of them depended on anything before them. They go out in
+one round now — the same commands, critical path 10 to 3, and ten of them
+used to leave in the shell's own first turn where twenty-three do now — and
+in a rig that runs the real store modules with the bridge instrumented,
+lib.loaded lands at 53 ms instead of 85 at a 6 ms round trip and 62 instead
+of 148 at 20 ms. Those are a desktop rig's milliseconds with the round trip
+swept rather than measured; the phone's own numbers are unproven until the
+walk prints bootMs and bootLibMs.
+
+The behaviour is meant to be identical. loadLibrary's only movable part was
+lib.error, which has two writers and used to be decided by the order they were
+awaited in; the two messages are now carried out of the round and applied in
+that same order, so a failing library still shows the library's message. Every
+combination of which of the five reads fails, over six latency shapes, comes
+out identical to the old code. bindSlsk still does not return until every
+handler is up, so connectStored cannot let a fast connected state land with
+nobody listening, and bindEvents still hands back the transport's unlisten and
+still rejects only when the transport is the one that failed.
+
+src/lib/boot.js is the project's first launch instrument — one counter every
+invoke and every listen passes, sealed at the first frame the shell paints and
+never re-opened, so a probe landing a second and a half later still reads the
+launch. perf.mjs measures frames; nothing measured the launch. The mock walk's
+Home step now holds a budget against it and both walks print bootCalls,
+bootSync, bootMs and bootLibMs on every step. bootSync is the clause with no
+clock in it: a call that waits on the one before it can only issue its first
+in the shell's own turn, so a chain put back in a queue falls under the floor
+whatever the machine is doing. A bootCalls of -2 means __ss.boot is not there
+at all, which is the census itself being broken rather than the app.
+
+One import line goes with it: Sheet.svelte's `import * as api`, the only one
+of the ten dead imports this round turned up whose reason is the bundle at
+all. Rollup already drops an unreferenced NAMED import, so a dead name on an
+import line is hygiene rather than bytes; a namespace import is the one shape
+tree-shaking cannot see through, and this one was dead. It frees nothing on
+its own — twenty-nine other files in the phone's graph hold the same module
+the same way, so api.js is pinned into the chunk whatever Sheet.svelte does —
+but it is the only one of the ten that belongs to a round about weight. The
+nine that are drift go out with the sweep in the round after this one.
+
+Two things were looked at and left alone, both written down in ANDROID.md
+rather than half-done. Home's per-artist catalog walk is the deepest chain in
+the app, and that serial walk is the Deezer and MusicBrainz pacing, not an
+oversight. And the follows really are read twice at launch, but the obvious
+guard does not work: Home's effect calls loadHome with force the first time
+they land, so the guard would never fire. One small local read, left for a
+round that can do it properly.