Delete TRANSCRIPT_RENDERING.md, which was all finished work

The file was a week's record of the transcript work, and everything in its
architecture, techniques and rejected sections has landed -- so it was a log
of how the code got here, which the code's own comments and AGENTS.md
already carry. Kept only what existed nowhere else: stream-bench.sh,
trace-draw.sh and the two emulator-loop traps go to AGENTS.md beside
transcript-bench.sh, along with the standing rule to run the benches either
side of a transcript change; GrapheneOS's broken System Tracing goes to
~/.claude/MACHINE.md, since it is about the phone rather than this project.

Its one unfinished item -- the reconnect loop after a restart onto a
streaming session, which may already have been fixed by the restore's
one-event-per-request fix -- moves to TODO.md.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

AGENTS.md

@@ -5,11 +5,6 @@ replacing the Claude app for daily use. Rust/Axum backend on the desktop,
 Kotlin/Compose Android app, WireGuard + pinned self-signed TLS + bearer token
 between them.
 
-**`TRANSCRIPT_RENDERING.md` is the record of the transcript work** --
-measurements, techniques, the harness, and the ordered list of what is
-next. Read it before touching anything under `Markdown*.kt`,
-`Transcript*.kt` or `SessionScreen.kt`'s list.
-
 **`PLAN.md` is the design source of truth.** Read it before building or
 changing anything structural. It records every decision with its date, its
 rationale, and the alternatives that were rejected and why — keep that habit
@@ -370,7 +365,7 @@ first if a remote spawn ever mangles an argument.
   **An inline code chip is drawn behind the text** rather than as the
   renderer's span background, because a span background is part of the
   text's own drawing and hid the selection under it -- see
-  `appendCodeChip` in `MarkdownLinks.kt` and TRANSCRIPT_RENDERING.md.
+  `appendCodeChip` in `MarkdownLinks.kt`.
 - **A session can be moved to another directory** from the settings dialog
   (`POST /sessions/{id}/cwd`). It stops the process, because a working
   directory is settled at spawn; the next message starts it in the new one.
@@ -523,7 +518,29 @@ first if a remote spawn ever mangles an argument.
   the in-app copy button produces, whose `on screen:` line names what the
   viewport was actually holding. Compare two runs of it with the same
   gestures; the emulator's absolute frame times transfer nothing, the
-  report's accounting does.
+  report's accounting does. Run it either side of any change under
+  `Markdown*.kt`, `Transcript*.kt` or `SessionScreen.kt`'s list, and put the
+  report in the commit; the numbers that move first are the worst
+  `record: one block`, the reparse mean while streaming, and the draw
+  phase's accounting line.
+- **`app/stream-bench.sh [-k] FILE` is that measurement for a reply still
+  arriving.** It opens the first session, taps "Jump to latest" so the list
+  is pinned to the newest end, resets the report, sends FILE, waits for the
+  transcript to stop growing, and prints. Both of those are corrections to a
+  first version that measured nothing: a transcript parked further back never
+  redraws while a reply streams into it, and a session is idle at *both* ends
+  of a turn, so polling for idle answers before the turn has started.
+- **`app/trace-draw.sh` names what a scrolling frame spends inside the
+  framework**, from `atrace` text output with no trace processor needed. It
+  is how the cost of a layout node per link was attributed to the framework
+  rather than guessed at.
+- **Two traps in the emulator bench loop**, each of which cost a run.
+  `adb shell pm clear` removes the enrolment and the notification permission
+  along with the saved anchors, so the next run measures a permission dialog
+  -- re-enrol with the command `ui-sandbox.sh` prints, and
+  `pm grant ... POST_NOTIFICATIONS`. And a saved scroll anchor is per session
+  id, so the only way two builds start a scroll from the same place is a
+  *fresh session for each*.
 - **`ai-server --delay MS` holds every response back.** Over the tunnel a
   phone's requests take tens to hundreds of milliseconds, and several
   faults live entirely in what the app does *while* one is outstanding. On