Make input-line prompt suggestions (ghost text) togglable -- indistinguishable from human input in tmux captures

Problem

Claude Code renders dim autocomplete "ghost text" (suggested prompts/continuations) on the interactive input line. There is no setting, environment variable, or /config option to disable it.

For single-user interactive use this is a nice affordance. For multi-agent tmux orchestration it is a genuine operational hazard:

• tmux capture-pane -p strips ANSI styling, so a machine-generated suggestion is byte-identical to a human-typed draft sitting on the input line.
• In an orchestrator/worker topology (one coordinating session supervising several claude panes), the input line is a real communication channel: humans type into worker panes, and coordinating agents read panes to deliver those messages. Ghost text pollutes that channel with plausible, context-aware, machine-written "instructions."
• In practice the suggestions frequently pre-echo the exact pending decision (a ship/no-ship call, an approval, a deploy command), because they are generated from the same context. We have logged 35+ "forged instructions" in a single day, including fake approvals of in-flight decisions and fabricated sign-offs impersonating the coordinating session's message format.

Every serious multi-session operator we know of ends up building the same defense: a styling-aware sweep tool (capture-pane -e + SGR classification) to distinguish dim ghost text from real human drafts before acting on anything found in a pane. That works, but it is a hand-rolled safety layer around a feature that cannot be turned off.

Ask

A supported off-switch (any of):

• a settings.json key (e.g. "inputSuggestions": false), or
• an environment variable (e.g. CLAUDE_CODE_DISABLE_INPUT_SUGGESTIONS=1), or
• a /config toggle.

Even just making it togglable would remove the hazard class entirely for orchestration users while keeping the affordance for everyone else. A distinguishable render (e.g. a stable marker prefix in the raw cell content) would be a weaker but still useful alternative.

Environment

• Claude Code 2.1.219, macOS (darwin), tmux multi-pane operation
• Reproduce: open claude in a tmux pane, let a suggestion render, tmux capture-pane -p -- the suggestion is indistinguishable from typed input.