iris: keyboard-wipe fix, dp unit for crisp text, header background (2026-09-06)

README.md

@@ -151,3 +151,50 @@ report -- "copy this and send it to Iris" via the existing Copy button.
 
 Full account, including what's still unverified on a real phone, in
 `docs/RUST.md`'s P0 box in the `ai-app-2` repo (`rustify` branch).
+
+## 2026-09-06, later still: keyboard-wipe fix, a density unit for crisp text, header background
+
+Iris's report on the previous rebuild, with screenshots: text now the
+right size but **blurry**; opening the keyboard still **wipes every
+glyph** (rectangles stay, only text disappears); the **header buttons
+have nothing behind them and overlap the transcript text**.
+
+- **Keyboard wipe**: `surface_changed` fires on every surface resize, not
+  only a genuinely new surface -- showing the keyboard under
+  `adjustResize` is exactly such a resize. It was rebuilding the whole
+  renderer (a fresh, empty glyph atlas) every time, while the CPU-side
+  glyph cache kept coordinates into the *old* atlas. Fixed: reuse the
+  existing renderer's device/atlas/buffers and only reconfigure the
+  surface when one is already live. Confirmed on this checkout's own
+  emulator two ways (a forced display resize and an actual soft-keyboard
+  open) -- text stayed on screen both times.
+- **Blur**: the previous fix's global "logical size" stretch (window
+  divided by density, then displayed stretched back up) rasterised each
+  glyph small and displayed it bigger than it had texels for. Fixed with
+  the density-independent length unit Iris asked for the same day (a new
+  `dp` alongside the existing physical-pixel and relative lengths,
+  resolved against the display's density at layout time) -- text now
+  rasterises at the display's real physical resolution.
+- **Header**: only each button's own coloured rect painted anything, so
+  gaps between/around them showed the black clear colour one layer back,
+  and the row's reserved height did not match the (now density-correct)
+  transcript below it. Fixed with an opaque panel behind the whole row
+  and every header size moved onto the new `dp` unit.
+- **New**: the bench build now auto-captures a diagnostics report ~500ms
+  after the keyboard opens (logged, copied to the clipboard, and shown in
+  a plain overlay with Copy/Close over the running app) -- so a report
+  can come back even if a keyboard-triggered regression is still
+  happening.
+
+**Not fully verified.** This build has not been run on Iris's actual
+phone. It was verified end to end on this checkout's own emulator
+(`run-bench.sh`, no crash, 24/24 swipes, 400/400 streamed events;
+before/after screenshots for the two keyboard-resize tests above). While
+verifying, a **separate, not-yet-fixed issue turned up**: after a
+keyboard-triggered resize, the header row appeared to render a second
+time, out of place, inside the transcript area, and a tap meant for the
+message field below landed on a header button instead (a benchmark run
+started unexpectedly). Not root-caused, and not confirmed to be caused by
+this pass's changes rather than something pre-existing -- worth watching
+for on the phone and reporting back if seen. Full account in
+`docs/RUST.md`'s P0 box in the `ai-app-2` repo (`rustify` branch).