feat: migrate 12 personal skills + add build/install scripts

- skills/: editable sources for all 12 personal skills (caveman family,
  find-skills, project-bootstrap, task-status-wiki, using-context7,
  using-markitdown, wiki-maintainer, compress)
- dist/: built .skill archives, committed (cross-machine deploy without
  needing zip on the target)
- scripts/build.sh + build.ps1: zip skills/<name>/ into dist/<name>.skill;
  Windows fallback uses .NET ZipArchive (PS 5.1 Compress-Archive writes
  backslashes that break extraction on *nix)
- scripts/install.sh: copy skills/<name>/ into ~/.claude/skills/<name>/
  ($CLAUDE_SKILLS_DIR overrides target)
- .wiki/source/repo-layout.md, build-notes.md: design + gotchas
- .gitignore: keep dist/ tracked

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

skills/caveman-commit/SKILL.md

@@ -0,0 +1,65 @@
+---
+name: caveman-commit
+description: >
+  Ultra-compressed commit message generator. Cuts noise from commit messages while preserving
+  intent and reasoning. Conventional Commits format. Subject ≤50 chars, body only when "why"
+  isn't obvious. Use when user says "write a commit", "commit message", "generate commit",
+  "/commit", or invokes /caveman-commit. Auto-triggers when staging changes.
+---
+
+Write commit messages terse and exact. Conventional Commits format. No fluff. Why over what.
+
+## Rules
+
+**Subject line:**
+- `<type>(<scope>): <imperative summary>` — `<scope>` optional
+- Types: `feat`, `fix`, `refactor`, `perf`, `docs`, `test`, `chore`, `build`, `ci`, `style`, `revert`
+- Imperative mood: "add", "fix", "remove" — not "added", "adds", "adding"
+- ≤50 chars when possible, hard cap 72
+- No trailing period
+- Match project convention for capitalization after the colon
+
+**Body (only if needed):**
+- Skip entirely when subject is self-explanatory
+- Add body only for: non-obvious *why*, breaking changes, migration notes, linked issues
+- Wrap at 72 chars
+- Bullets `-` not `*`
+- Reference issues/PRs at end: `Closes #42`, `Refs #17`
+
+**What NEVER goes in:**
+- "This commit does X", "I", "we", "now", "currently" — the diff says what
+- "As requested by..." — use Co-authored-by trailer
+- "Generated with Claude Code" or any AI attribution
+- Emoji (unless project convention requires)
+- Restating the file name when scope already says it
+
+## Examples
+
+Diff: new endpoint for user profile with body explaining the why
+- ❌ "feat: add a new endpoint to get user profile information from the database"
+- ✅
+  ```
+  feat(api): add GET /users/:id/profile
+
+  Mobile client needs profile data without the full user payload
+  to reduce LTE bandwidth on cold-launch screens.
+
+  Closes #128
+  ```
+
+Diff: breaking API change
+- ✅
+  ```
+  feat(api)!: rename /v1/orders to /v1/checkout
+
+  BREAKING CHANGE: clients on /v1/orders must migrate to /v1/checkout
+  before 2026-06-01. Old route returns 410 after that date.
+  ```
+
+## Auto-Clarity
+
+Always include body for: breaking changes, security fixes, data migrations, anything reverting a prior commit. Never compress these into subject-only — future debuggers need the context.
+
+## Boundaries
+
+Only generates the commit message. Does not run `git commit`, does not stage files, does not amend. Output the message as a code block ready to paste. "stop caveman-commit" or "normal mode": revert to verbose commit style.