fix: correct the pi wheel docs and comments (release review)

The gate comment in terminal-ui.js said a stale-false flag falls through
to the PageUp/PageDown fallback, which is false for pi since the second
commit of this PR removed that fallback. The FOOTGUN comment above it made
the same claim. Say what happens instead.

"Every pi below 1.0.0 emits no mouse enables" was too absolute: regular
was the default there, but fullscreen exists from 0.84.0. Measured with
--tui-mode fullscreen under tmux on 0.84.1, 0.85.0, 0.86.0 and 0.99.2:
alternate_on=1, mouse_any_flag=1, mouse_sgr_flag=1. Default settings on
0.99.2 report all 0.

Document that Wheel Scrolls Local History leaves the wheel dead in
fullscreen pi (wiki, integration guide, changeset), add a pi block to
Troubleshooting, cross-reference the accepted exception from the dead
gesture rule in architecture-invariants, and mark the pi-integration-plan
passages this PR reversed as superseded.

Comments and docs only, no runtime change.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/wiki/Settings-Reference.md

@@ -49,7 +49,7 @@ supervised by systemd or launchd; npm installs report as non-updatable. See
 | Keep Size Under Keyboard      | On                   | For local Claude sessions, the on-screen keyboard no longer resizes the session: the terminal keeps its rows and the view scrolls so the prompt sits just above the keyboard. Resizing made Claude reprint its screen and drop transcript lines from history. Codex, Claude's fullscreen mode, remote and Docker sessions resize as before. See [Mobile Guide](Mobile-Guide). |
 | CJK Input                     | Off                  | IME composition through a dedicated text field.                        |
 | Extended Keyboard Bar         | Per device           | Which accessory bar phones get. Shell sessions override it while they are active. |
-| Wheel Scrolls Local History   | Off                  | Keeps the wheel on the local buffer instead of forwarding it to the CLI. |
+| Wheel Scrolls Local History   | Off                  | Keeps the wheel on the local buffer instead of forwarding it to the CLI. Fullscreen pi leaves that buffer empty and has no paging fallback, so with this on the wheel does nothing there. |
 | Auto Copy Selection           | Off                  | Copies highlighted terminal text to the clipboard the moment you finish selecting it. Ctrl+C still copies on demand. |
 | Trim The Pane Margin On Copy  | On                   | Takes the left margin a full-screen agent CLI paints down its own edge off a copy, so the text pastes flush. Each CLI declares its own width, and the strip never exceeds the indent every selected line shares, so nesting is kept. Claude Code and Codex declare a margin; a shell does not. |
 | Normal / Bold font weight     | xterm defaults       | Per device, each slot from 100 to 900. The bundled JetBrains Mono renders every step, so a lighter normal weight makes Claude's bold headings stand out. Applies live to the terminal, both echo overlays and open team panes. |

docs/wiki/Troubleshooting.md

@@ -221,6 +221,17 @@ Things to try:
 Codex with mouse tracking on gets the wheel forwarded like fullscreen Claude; otherwise
 it pages its transcript or scrolls locally, while `Shift+Wheel` always uses local scrollback.
 
+### The wheel does nothing in a pi session
+
+Fullscreen pi, the default since pi 1.0.0, scrolls its own transcript, so the wheel is
+forwarded to it while it has mouse tracking on. If the wheel does nothing, turn off
+**Wheel Scrolls Local History**: that setting keeps the wheel on a local buffer pi leaves
+empty, and pi has no paging fallback. `PageUp` and `PageDown` on a keyboard still reach pi.
+
+Codeman strips pi's mouse enables, so a drag selects text in the browser rather than using
+pi's own selection or scrollbar drag. With `tuiMode: regular` pi is inline and the wheel
+scrolls local history.
+
 ### Selected text is invisible on a light skin
 
 Update. Every skin named its selection colour under a key xterm renamed in v5, so the four