Give the mouse back, retire the follow controls, update Claude per session

Three things the terminal was getting wrong.

**A program that grabs the mouse and dies used to freeze the tab.** A TUI sets
DECSET ?1000/?1002/?1003; if it exits without resetting them, xterm keeps
routing clicks, drags and — under ?1003 — every pointer *move* to the PTY.
Text selection dies and escape bytes flood the prompt. The only exit was
closing the tab. `TerminalView` now reconciles a flag against
`term.modes.mouseTrackingMode` in the `term.write()` callback — the mode only
changes because the container printed a sequence, so one check per write
catches every transition with no polling — and `Ctrl+Shift+X` or a status-bar
button writes the resets back through `term.write`, never `sendInput`: the
reset belongs to xterm's parser, and a still-live TUI told about it would just
re-grab on its next repaint.

The control is in the status bar deliberately. Mouse tracking is the *normal*
state of htop, vim, lazygit and Claude Code, so a badge over the terminal
would be on screen for the whole life of those programs and would swallow
clicks aimed at their own top-right corner. `macOptionClickForcesSelection` is
also on now: xterm's force-select is Shift everywhere except macOS, where it
is Option and is gated behind that option, which defaults to false — so until
now Mac users had no way to select text while a program held the mouse.

**"Following" and "Jump to Current" are gone.** Claude Code draws on the
alternate screen, which has no scrollback, so `viewportY` always equalled
`baseY` and neither control could do anything. They did still work in bash
tabs; xterm's native follow covers that, and the per-write `scrollToBottom()`
went with them because it fought exactly that. What remains, on activate and
after a refit, now samples `viewportY >= baseY` *before* the fit, so opening
the Notes dock no longer yanks a reader to the tail.

**`claude update` runs before every Claude session, not just at container
start.** Containers here stop/start and often just keep running, so a
long-lived one never re-checked. Both copies take the same flock: the
entrypoint prints "container ready" only after its own update finishes, so
opening a tab immediately would otherwise run two updaters against the same
~/.claude/bin, with `|| echo` hiding a half-written install one line before
`exec claude` ran it.

This turns the non-Bedrock path from a bare argv into a `bash -c` wrapper, so
flags and session names are shell-interpolated now and must go through
`shell_quote_arg`.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0145mQi9NZiCDrznBUEEDE4n

HOW-TO-USE.md

@@ -243,7 +243,7 @@ Anthropic-backend project uses that token without its own login. See
 │             │  │                                                  │  │
 │             │  └──────────────────────────────────────────────────┘  │
 ├─────────────┴────────────────────────────────────────────────────────┤
-│  2 project(s) · 1 running · 2 terminal(s)          Jump to Current ↓ │
+│  2 project(s) · 1 running · 2 terminal(s)                      Notes │
 └──────────────────────────────────────────────────────────────────────┘
 ```
 
@@ -268,8 +268,8 @@ Anthropic-backend project uses that token without its own login. See
 - **Main area** — Shows the active tab: a Project Home view or an xterm.js terminal. With no tabs
   open you get a welcome screen with Docker/image/project readiness checks.
 - **StatusBar** — Counts of total projects, running containers and open terminal sessions; the
-  **Jump to Current ↓** button when a terminal is scrolled up; and the microphone button when
-  speech-to-text is enabled.
+  **🖱 Mouse captured — release** button while a program in the terminal is holding the mouse; the
+  **Notes** toggle; and the microphone button when speech-to-text is enabled.
 
 ---
 
@@ -1224,9 +1224,31 @@ Programs inside the container can copy text to your host clipboard. When a conta
 
 You can paste images from your clipboard into the terminal (Ctrl+V / Cmd+V). The image is uploaded to the container as `/tmp/clipboard_<timestamp>.png` and the file path is injected into the terminal input so Claude Code can reference it. A toast notification confirms the upload.
 
-### Jump to Current
+### Scrolling
 
-When you scroll up in the terminal to review previous output, a **Jump to Current** button appears in the bottom-right corner. Click it to scroll back to the latest output.
+Scrolling is the terminal's own: scroll up to read back and it holds position, scroll to the
+bottom and it follows new output again. There is no follow toggle — an earlier **Following /
+Paused** control and a **Jump to Current** button were retired once they stopped doing anything
+useful, because Claude Code draws its interface on the alternate screen, which has no scrollback
+for them to act on.
+
+### When the mouse stops working
+
+Some programs ask the terminal for the mouse, so that clicks and drags go to the program instead
+of selecting text. If one of them exits without handing the mouse back, the terminal looks stuck:
+you cannot select text, and stray characters can appear as you move the pointer.
+
+A **🖱 Mouse captured — release** button appears in the status bar whenever a program holds the
+mouse. Click it, or press **Ctrl+Shift+X**, to take the mouse back. Nothing is sent into the
+container — only the terminal's own state is reset.
+
+Note that holding the mouse is normal for programs like `htop`, `vim` and Claude Code itself, so
+the button is showing most of the time you are in one. It is there for when a program exits
+without handing the mouse back and the terminal is left stuck; releasing while a program is still
+running just takes the mouse away from that program.
+
+To select text *without* taking the mouse back, hold **Shift** while dragging — or **Option** on
+macOS.
 
 ### Files