feat(cli): skill install targets + remove custom install in favor of vercel-labs/skills (#177)

## Summary

**Skill install targets (original):**
- Add project-level skill install targets: Windsurf, Cline, Roo Code, Trae (opt-in via flag)
- Split install logic into global vs project-level
- Fix lint false positive: timed tags with `data-composition-id` no longer flagged by media rule

**Skill system cleanup (folded from #189):**
- Delete `install-skills.ts` (~485 lines) — remove custom installation wrapper entirely
- Strip skill logic from `init` — no more project-level `.claude/skills/` copies, no `--skip-skills` flag; replaced with post-scaffold message: `npx skills add heygen-com/hyperframes`
- Front-load SKILL.md trigger words — all 5 skill descriptions rewritten so activation language comes first (~150 chars)
- Update CLAUDE.md — install instructions now point to [vercel-labs/skills](https://github.com/vercel-labs/skills)
- Fix `.claude/settings.json` — pre-commit hook changed from `pnpm` to `bun`

## Test plan

- [ ] `npx hyperframes skills` → "Unknown command skills"
- [ ] `npx hyperframes init test --template blank --non-interactive --skip-transcribe` → prints `npx skills add heygen-com/hyperframes`
- [ ] `grep -r "install-skills" packages/cli/src/` → no results
- [ ] All 5 `skills/*/SKILL.md` have front-loaded descriptions

🤖 Generated with [Claude Code](https://claude.com/claude-code)

skills/hyperframes-compose/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: hyperframes-compose
-description: Create HyperFrames HTML video compositions. Use when asked to create a video, build an animation, make a composition, add a title card, or generate any HTML-based video content for HyperFrames.
+description: Create video compositions, animations, title cards, or overlays in HyperFrames HTML. Use when asked to build any HTML-based video content.
 ---
 
 # Compose Video