refactor: split packs out of engine repo (one repo per pack)

[anthroos]

Summary

The seed pack at experiences/d49e0997/ moved to its own public repo: anthroos/exp-inbound-acquisition-with-free-pilot. The engine repo no longer bundles packs.

Why

Before	After
Engine repo bundled the seed pack at experiences/<uuid>/	Each pack is its own GitHub repo named exp-<slug>
Catalog == this repo's experiences/ directory	Catalog == set of exp-* repos, listed at openexp.ai/use
Author wanting to publish: PR against anthroos/openexp	Author publishes to their own repo, opens an issue here to be added to catalog

Three reasons:

• Authors own their pack lifecycle. Issues, license, versioning, attribution — all on the author's repo, not negotiated through the engine.
• Engine stays focused. This repo is the runtime. Pack content is content.
• Future automated registry is trivial. Scan exp-* repos under known orgs, aggregate meta.yaml summaries. Naming convention enables this.

What changed in this repo

• Removed experiences/d49e0997/ entirely (4 files, 478 lines). History preserved in git log; canonical artifact lives in the new pack repo.
• README.md — "Publishing an Experience" section rewritten for the new repo shape; install command updated to git clone <pack-repo> + symlink. Status section now references the new pack repo.
• docs/roadmap.md — Section 4 (Marketplace browse + install) reflects the new model. Adds a "Automated catalog index" row marked ❌ as the explicit next gap. Demo-path install commands updated.
• docs/skill-architecture.md — "Storage vs install" table: storage is now github.com/<owner>/exp-<slug>, not experiences/<uuid>/. Install flow rewritten with clone + symlink.
• docs/publishing-a-pack.md (new) — author guide. Schema, anonymization rules, why per-pack repo, how to announce.

Backward compat

Existing user installs continue to work — install path (~/.claude/skills/openexp:<author>:<slug>/) is unchanged. Only the source-of-clone moves from this repo to the pack repo.

Test plan

• Fresh install path works:

  git clone https://github.com/anthroos/exp-inbound-acquisition-with-free-pilot.git
  ln -s "$PWD/exp-inbound-acquisition-with-free-pilot" \
    ~/.claude/skills/openexp:ivan-pasichnyk:inbound-acquisition-with-free-pilot
  

• openexp-use skill discovers the pack on next Claude Code session
• No broken links in README / docs (grep for experiences/d49e0997, experiences/<uuid>)