[FEATURE] Option to hide the worktree card(s) shown in a session

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

In the Claude Code desktop app, a session associated with git worktrees shows worktree card(s) in the session view. There is no way to hide, collapse, or dismiss them. In repos where .claude/worktrees/* checkouts accumulate across phases of work, the cards occupy space in every session and imply an active worktree association even when the session is not actually working in that worktree (see #78664 for a session pinned to a stale worktree path it was not using).

Proposed Solution

• A dismiss control on each worktree card, and/or
• a setting to hide worktree cards globally (or show them collapsed by default).

A per-session dismissal should persist for that session.

Alternative Solutions

• Removing the worktree itself (git worktree remove) - heavy-handed, and wrong when the worktree is still needed by other sessions or as a preserved branch checkout.
• Ignoring the cards - they still take up space in every session view.

Priority

Low - Nice to have

Feature Category

Other

Use Case Example

A monorepo with several long-lived .claude/worktrees/* checkouts (one per plugin/phase). Sessions regularly show card(s) for worktrees the session is not using; hiding them would cut noise and avoid implying the session is operating in that worktree.

Additional Context

Related: #78664 (session default working directory pinned to a stale worktree path - the flip side of this UI: the directory that matters is invisible, while cards for directories that do not matter are always visible), and #60097 (request to display the current worktree/cwd in the desktop UI - accurate cwd display and hiding irrelevant worktree cards are complementary). Environment: Claude Code desktop app, Windows 11.