perf(native): optimize iOS transcript refresh and add frame profiling

Preserve hosted rows while propagating current SwiftUI environments and render captures. Add differential refresh regressions, opt-in real-clock iOS/Android profiling, and reproducible performance results.

Validation: typecheck; CLI/hub/web/shared/relay suites (Web rerun with NODE_OPTIONS=--no-experimental-webstorage for Node 26/jsdom compatibility); existing iOS Debug/Release and Android regression runs.

android/scripts/scroll-frame-summary.sql

@@ -0,0 +1,37 @@
+-- Perfetto trace_processor: -q android/scripts/scroll-frame-summary.sql TRACE
+-- Present cadence only during real drags; never divide frame count by idle time.
+-- FrameTimeline Prediction Error / SurfaceFlinger Scheduling classifications in
+-- an emulator are not a reliable app-jank score. Report app deadlines separately.
+WITH phases AS (
+    SELECT id, name, ts, dur FROM slice WHERE name GLOB 'HapiScroll:*'
+), gestures AS (
+    SELECT p.name AS phase, g.id, g.ts, g.dur
+    FROM phases p JOIN slice g
+      ON g.name = 'HapiGesture' AND g.ts >= p.ts AND g.ts + g.dur <= p.ts + p.dur
+), frames AS (
+    SELECT g.phase, g.id AS gesture, a.ts + a.dur AS presented,
+           a.jank_type, a.on_time_finish
+    FROM gestures g JOIN actual_frame_timeline_slice a
+      ON a.ts + a.dur BETWEEN g.ts AND g.ts + g.dur
+    WHERE a.layer_name GLOB '*run.hapi.companion*'
+      AND a.dur > 0 AND a.present_type != 'Dropped Frame'
+), intervals AS (
+    SELECT *, (presented - LAG(presented) OVER (PARTITION BY gesture ORDER BY presented)) / 1e6 AS gap_ms
+    FROM frames
+)
+SELECT phase,
+       COUNT(DISTINCT gesture) AS gestures,
+       COUNT(*) AS presented_frames,
+       ROUND(1000 * COUNT(gap_ms) / SUM(gap_ms), 2) AS present_cadence_fps,
+       ROUND(PERCENTILE(gap_ms, 50), 2) AS present_p50_ms,
+       ROUND(PERCENTILE(gap_ms, 95), 2) AS present_p95_ms,
+       ROUND(PERCENTILE(gap_ms, 99), 2) AS present_p99_ms,
+       SUM(CASE WHEN on_time_finish = 0 THEN 1 ELSE 0 END) AS app_late_finish,
+       SUM(CASE WHEN jank_type LIKE '%App Deadline Missed%' THEN 1 ELSE 0 END) AS app_deadline_missed
+FROM intervals GROUP BY phase ORDER BY phase;
+
+-- Must have all requested phases: a too-small ring buffer silently loses setup
+-- and early scrolls even though the trace is otherwise parseable.
+SELECT name FROM slice WHERE name GLOB 'HapiScroll:*' ORDER BY ts;
+
+SELECT name, value, description FROM stats WHERE severity != 'info' AND value != 0;