[FEATURE] Support panel parameter in claude://resume deeplink to open plan pane

Bug Description
The undocumented claude://resume?session=<id> deeplink works well to
transfer a Claude Code terminal session into Claude Desktop — I use
it from a PreToolUse:ExitPlanMode hook so the plan can be
reviewed/revised in the chat UI instead of via the markdown file.

The remaining gap: when Desktop opens, it lands on the chat with the
plan-pane collapsed. There's no way to script "open Desktop with the
plan pane already shown" because:

• The resume URL handler in app.asar only reads the session param,

then navigates to /local_sessions/<id> — no panel/view param is
accepted.

• No menu item exists for the plan pane (grepped all {label:"..."}

entries in the bundle).

• No keyboard shortcut is assigned that I can find in Settings.

Either of these would close the gap, in order of preference:

1. Accept a query param: claude://resume?session=<id>&panel=plan (or

view=plan) — opens Desktop with the plan pane already expanded.
Cleanest; works for any automation, not just hooks.

1. Add a View → Show Plan menu item with a default accelerator (e.g.

⌘⇧P). Lets users assign their own via System Settings → Keyboard
Shortcuts, and gives AppleScript a stable hook.

Use case: ExitPlanMode hooks that route the user to Desktop to revise
plans interactively. Without this, the workflow ends with a
one-click stub instead of being fully automated.

Environment Info

• Platform: darwin
• Terminal: webstorm
• Version: 2.1.143
• Feedback ID: 142e75f3-395e-458c-a367-d0a1f48de6c6