feat: add init-repo skill

skills/init-repo/SKILL.md

@@ -0,0 +1,114 @@
+---
+name: init-repo
+description: >
+  Initialize a brand-new GitHub repository and land in a ready-to-work checkout: create the
+  remote with gh repo create, clone it under the ghq root, push a single empty "chore: init"
+  commit as main's root, then cut a fixed `bootstrap` branch and stop there. Use when starting
+  a repository from zero ("new repo", "repo 作って", "リポジトリ新規作成"). Init only — no
+  README/LICENSE scaffolding, no PR, no CI or branch protection; those belong to later steps
+  on the bootstrap branch.
+---
+
+# Init Repo
+
+Goal: Go from "no repository" to "an empty repository with a clean root commit,
+checked out locally on a `bootstrap` branch, ready for the first real work".
+
+The design intent: `main` starts as a single empty commit and stays clean.
+Everything that makes the repository useful — README, license, tooling — arrives
+later via pull requests from the `bootstrap` branch. This skill only prepares
+that starting line; it never writes project files itself.
+
+## Why an empty init commit
+
+A root commit with no files gives every later change — including the very first
+README — a parent to diff against, keeps `git rebase -i --root` and `git bisect`
+well-behaved, and means the actual scaffolding can go through a reviewable PR
+instead of being baked into the root.
+
+## Workflow
+
+### 0) Preconditions
+
+`gh auth status` and `ghq root` must both succeed. Surface errors and stop on
+failure.
+
+### 1) Gather the essentials
+
+From the user (or the conversation), determine:
+
+- **Repository name** — required.
+- **Visibility** — `--public` or `--private`. If not stated, ask; never guess.
+  Publishing a repository is outward-facing.
+- **Owner** — default to the authenticated user, resolved concretely with
+  `gh api user --jq .login` (a machine may hold several `gh` accounts). Only
+  ask when an organization is plausibly intended.
+- **Description** — optional; include only if the user provides one.
+
+Confirm the combination (`owner/name`, visibility) with the user before
+creating. This is the one confirmation gate in the flow.
+
+### 2) Create the remote
+
+```bash
+gh repo create <owner>/<name> --private|--public [--description "<desc>"]
+```
+
+Do not pass `--license`, `--gitignore`, `--add-readme`, or `--clone` — any of
+those would create a remote first commit and break the clean-root design.
+If the name already exists, `gh` errors; surface it and stop.
+
+### 3) Clone under the ghq root
+
+```bash
+ghq get <owner>/<name>
+```
+
+Cloning an empty repository warns; that is expected. Run everything after this
+inside the clone:
+
+```bash
+cd "$(ghq root)/github.com/<owner>/<name>"
+```
+
+### 4) Root commit on main
+
+The fresh clone has no commits yet, so HEAD is an unborn branch named by the
+local `init.defaultBranch` — branch commands like `git switch` misbehave on it.
+Point HEAD at `main` directly, then create the empty root commit and push:
+
+```bash
+git symbolic-ref HEAD refs/heads/main
+git commit --allow-empty -m "chore: init" -m "Co-Authored-By: <your harness's co-author line>"
+git push -u origin main
+```
+
+The second `-m` carries the `Co-Authored-By` trailer your harness convention
+specifies — this commit is authored through the agent, same as any other.
+
+### 5) Cut the bootstrap branch
+
+```bash
+git switch -c bootstrap
+```
+
+The branch name is fixed: `bootstrap`, always. Local only — it gets pushed
+when the first real work goes up (typically via `publish-pr`).
+
+### 6) Report
+
+Give the user the repository URL, the local path, and the current branch
+(`bootstrap`), and note that `main` holds exactly one empty commit.
+
+## Boundaries
+
+- **No project files.** README, LICENSE, justfile, `.gitignore` — all of it is
+  bootstrap-branch work owned by other skills (`build-readme`,
+  `build-justfile`) or the user.
+- **No PR.** Opening the first PR belongs to `publish-pr`.
+- **No CI / branch protection / repo settings.** Separate concerns, configured
+  once there is something to protect.
+- **Never proceed past step 1 without explicit confirmation** of owner, name,
+  and visibility — repository creation is public-facing and annoying to undo.
+- **Stop and explain** if `gh`, `ghq`, or auth is missing, or the target name
+  already exists, rather than improvising.