Add worktree create/remove VSCode tasks for cpp-library's own repo

[sean-parent]

Summary

• Adds a root .vscode/tasks.json with the "worktree: create" / "worktree: remove" tasks (best-effort tokensave integration), mirroring what templates/.vscode/tasks.json already gives to consumer projects (PR Add worktree create/remove VSCode tasks #24) — but without the CMake-preset/cleanup tasks, since cpp-library's own root has no CMakePresets.json.
• Fixes a .gitignore gap: .claude/worktrees/ wasn't ignored at the repo root, so worktrees created there (by this new task or by the EnterWorktree tool) showed up as untracked content. Added .claude/worktrees/ and .tokensave, matching the consumer template's entries.
• Adds design + plan docs under docs/superpowers/ following this repo's established convention for this kind of change.

Test plan

• cmake -P tests/install/CMakeLists.txt — 33/33 pass (unaffected by this change; run to confirm no regression)
• cmake -P tests/setup/test_setup_version_resolution.cmake — passes
• Verified .vscode/tasks.json is valid JSON with the expected 2 tasks / 1 input
• Verified the two tasks are byte-identical to their counterparts in templates/.vscode/tasks.json
• Verified git status --porcelain .claude/ is clean after the .gitignore fix
• Exercised the git worktree add/remove + best-effort tokensave command in a scratch repo (bash form); create always succeeded (exit 0) including when tokensave was substituted with a nonexistent binary name
• Note: this machine has a personal global git post-checkout hook (~/.config/git/hooks/post-checkout, set via core.hooksPath) that auto-runs real tokensave bookkeeping on every checkout, independent of this repo. That caused git worktree remove (without --force) to occasionally fail on leftover .tokensave/ state during my scratch testing — this is identical, pre-existing behavior of the already-shipped, byte-identical consumer-facing task, not something introduced here, and not fixable from this repo.

🤖 Generated with Claude Code

---

Note

Low Risk
Developer tooling and ignore rules only; no runtime, build, or consumer-shipped template changes.

Overview
Brings the worktree: create / worktree: remove VS Code tasks to the cpp-library repo root so developers get the same workflow when this repo is the workspace—not only when consumer projects copy templates/.vscode/tasks.json. The new root tasks.json includes only the worktreeName prompt and those two shell tasks (optional tokensave + code --new-window), deliberately omitting CMake preset/cleanup tasks because this root has no CMakePresets.json.

Root .gitignore now ignores .claude/worktrees/ and .tokensave, aligning with the consumer template so worktrees under .claude/worktrees/ no longer appear as untracked noise.

Adds docs/superpowers/ design and implementation plan docs for this change; templates/ and CMake modules are untouched.

^{Reviewed by Cursor Bugbot for commit d8bff2a. Bugbot is set up for automated code reviews on this repo. Configure here.}

[Copilot]

Pull request overview

Adds repo-local developer tooling to make working with git worktrees in this repository match the already-established consumer template workflow.

Changes:

• Add root .vscode/tasks.json with worktree: create / worktree: remove tasks (and worktreeName input), aligned with templates/.vscode/tasks.json.
• Update root .gitignore to ignore .claude/worktrees/ and .tokensave to prevent worktree-related untracked noise.
• Add design + implementation plan docs under docs/superpowers/ documenting scope and constraints.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated no comments.

File	Description
docs/superpowers/specs/2026-07-16-cpp-library-worktree-tasks-design.md	Design/spec describing why root tasks are needed and what’s in/out of scope.
docs/superpowers/plans/2026-07-16-cpp-library-worktree-tasks-plan.md	Step-by-step implementation/verification plan for adding root tasks + ignore rules.
.vscode/tasks.json	New root VS Code tasks for worktree create/remove with best-effort tokensave integration.
.gitignore	Ignore entries for .claude/worktrees/ and .tokensave.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.