feat: version infra skills (1.0.0) + project-bootstrap manifest step

Six infra skills carry `version: 1.0.0` in frontmatter:
project-bootstrap, setup-context7, task-status-wiki, using-context7,
using-markitdown, wiki-maintainer. Bumped manually on SKILL.md edits;
semver — MAJOR breaks contract, MINOR adds, PATCH wording.

project-bootstrap gets a new Step 5.5 that writes
.wiki/concepts/bootstrap-manifest.md per project — skill + version + role
table read live from each delegated skill's frontmatter, not hardcoded.
The file is overwritten on re-bootstrap; for history, git log.

Why: when canonical layout for .wiki/ or .tasks/ changes, projects
bootstrapped under the old version drift silently. The per-project
manifest makes that drift debuggable instead of guesswork. Communication
and discovery skills (caveman family, find-skills, active-platform)
aren't versioned — their content is "good copy-paste" and snapshot
mismatch isn't a layout problem.

Wiki: .wiki/concepts/skill-versioning.md documents the convention;
index.md and log.md updated. .tasks/STATUS.md tracks (a/b/c) progress.

Setup/using split for wiki and tasks (commits b and c) follows.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.wiki/index.md

@@ -16,6 +16,7 @@ Catalog of all wiki pages. One line per page, organized by type. Updated on ever
 - [build-notes.md](concepts/build-notes.md) — why `build.ps1` exists alongside `build.sh`; PS 5.1 backslash-in-zip gotcha; how to extract a `.skill`
 - [context7-setup.md](concepts/context7-setup.md) — switched context7 from manual MCP entries to the official plugin; API key in `.mcp.json` as `--api-key`; now also captured as `setup-context7` skill (one-time install/migrate flow with key discovery)
 - [repo-layout.md](concepts/repo-layout.md) — flat `skills/`, committed `dist/`, bash + PowerShell scripts; install model
+- [skill-versioning.md](concepts/skill-versioning.md) — why infra skills carry `version: <semver>` in frontmatter and how `project-bootstrap` records them in a per-project manifest
 - [skill-vs-plugin.md](concepts/skill-vs-plugin.md) — when a bare SKILL.md is enough vs when you actually need a plugin (slash commands, hooks, sub-agents, MCP servers); concrete breakdown of `superpowers`
 - [wiki-realignment.md](concepts/wiki-realignment.md) — fixing `project-bootstrap` to create the Karpathy-canonical wiki layout