Persistent output verbosity setting (default collapsed tool output)

Problem

Every session starts with full tool output expanded (Edit diffs, Bash output, search results). Ctrl+O toggles collapsed/expanded, but resets each session. For users who primarily care about Claude's reasoning and summary text, the diffs and raw output are noise that requires constant toggling.

Requested Feature

A persistent setting in settings.json to control default output verbosity:

{
  "outputVerbosity": "collapsed"
}

Values: "expanded" (current default), "collapsed" (tool results folded by default, Ctrl+O to expand).

Stretch: per-tool display control

{
  "outputVerbosity": {
    "default": "collapsed",
    "Edit": "collapsed",
    "Bash": "collapsed",
    "WebSearch": "collapsed"
  }
}

Why This Matters

When reviewing a session with 10-20 tool calls, the signal (Claude's analysis and decisions) gets buried in the noise (raw diffs, command output, search results). The information is still there via Ctrl+O when needed, but defaulting to collapsed would make the conversational flow much easier to follow.

Current Workaround

Ctrl+O each session. No persistence.