Add human-focused README.md to every skill and bundle directory

Each README is written for a human audience, explaining:
- What the skill does (not what format it follows)
- What benefit the user gets from installing it
- Quick setup and usage patterns
- When to load/trigger the skill
- What scripts, references, and templates it ships

data-scientist already had a README — left unchanged.

48 READMEs added across all skill and bundle directories.

openlibrary-cli/README.md

@@ -0,0 +1,36 @@
+# Open Library — Book Metadata from the Terminal
+
+Search books and authors, look up works and ISBNs, and fetch detailed metadata from the public Open Library API. No API key, no registration — just works.
+
+## Why Install This Skill
+
+When your agent loads this skill, it can **access 50M+ book records** without any setup. That means:
+
+- **Search by keyword** — find books by title, author, or subject
+- **Look up by ISBN** — get detailed metadata for any ISBN
+- **Author details** — bio, birth/death dates, top works
+- **Work and edition info** — publication dates, languages, formats
+- **Filter and sort** — by language, year, rating, or new arrivals
+
+## What You Get
+
+| Directory | Purpose |
+|-----------|---------|
+| `SKILL.md` | Complete command reference with examples |
+| `scripts/openlibrary-cli` | CLI tool for the Open Library API |
+
+## Quick Start
+
+```bash
+openlibrary-cli search --query "dune"
+openlibrary-cli search --isbn "9780439358064"
+openlibrary-cli search-authors --query "asimov"
+```
+
+## Triggers
+
+Load this for book research, ISBN lookups, author information, or cataloging projects.
+
+## Requirements
+
+Python 3.8+ with `requests` library. No API key needed — fully public API.