Worktree status bar: 'Create PR' button should respect custom /pr skills and reflect merged state

Problem

When using a worktree session, the status bar shows a "Create PR" button that is hardwired to the built-in /create-pr flow. Two issues:

1. Button persists after PR is merged

Once a PR is created and merged for the branch, the "Create PR" button (with the +8 -8 diff stats) remains visible alongside the merged PR tracker row. This is confusing — it looks like there's still work to do.

Expected: The button should hide or change to "View PR" once a PR exists for the branch.

2. No way to remap to a custom skill

Many users define custom /pr skills (via .claude/skills/) that add project-specific steps before PR creation — linting, testing, migration validation, checking for already-merged PRs, etc. The built-in "Create PR" button bypasses all of this.

Expected: If a custom /pr or /create-pr skill exists in the project, the button should invoke that skill instead of the built-in flow. Or at minimum, offer a way to configure which skill the button triggers.

Screenshots

After merge — both the "Create PR" button and "Merged" status show simultaneously:

The top bar still shows the branch with +8 -8 and "Create PR", while directly below it shows PR #449 as "Merged". This is the confusing state.

Environment

• Claude Code desktop app (macOS)
• Using worktree sessions with custom /pr skill
• Opus 4.6

🤖 Filed with Claude Code