Fix skill path resolution and PyPI skill packaging.

[rosspeili]

Description

Fixes #13: SkillLoader.load_skill("category/name") failed after pip install because relative paths were resolved only next to the installed package (site-packages/skills/), not the user’s project. PyPI wheels also shipped mostly .py files, so bundled skills loaded with empty manifests.

What changed

Core (skillware/core/loader.py)

• Added _resolve_skill_path() with explicit search order:
  1. Existing path on disk (absolute or relative) that contains skill.py
  2. SKILLWARE_SKILL_PATH (multiple roots, os.pathsep-separated)
  3. skills/ under the current working directory, walking up to 6 parent dirs
  4. Bundled site-packages/skills/ (same layout as the repo registry)
• Clear FileNotFoundError listing paths tried when nothing matches.

Packaging (pyproject.toml, MANIFEST.in, skills/**/__init__.py)

• Version bump to 0.2.7
• include-package-data = true, MANIFEST.in (graft skills), and skills = ["**/*"] so wheels include manifest.yaml, instructions.md, card.json, and data files—no per-skill pyproject.toml entries when adding skills.
• Empty __init__.py on category packages and office/pdf_form_filler so setuptools includes the full skill tree.

Tests

• Loader: cwd skills/, SKILLWARE_SKILL_PATH, env-over-cwd precedence, registry manifest non-empty, wheel contains skill YAML.
• Issuer: test_registry_skills_have_packaging_init_files enforces __init__.py for new registry skills.

Docs & contributor guidance

• docs/usage/README.md — “Finding skills on disk”
• docs/introduction.md, docs/skills/README.md, path fixes in skill catalog pages
• CONTRIBUTING.md, templates/python_skill/README.md — packaging checklist (__init__.py, no pyproject edits per skill)
• README.md — pointer to path search order
• .gitignore — .ruff_cache/

Why

Environment	Before	After
Git clone / pip install -e .	Worked (package-adjacent skills/)	Same; project skills/ still found first
pip install in another app	Looked only under site-packages/skills/; incomplete bundles	Project ./skills/, env var, then bundled; full manifests in wheel

CI was unaffected in practice because it runs pytest from a full checkout; this aligns PyPI behavior with clone behavior.

How to verify

python -m flake8 .
pytest tests/
python -m pip wheel . --no-deps -w /tmp/wheels
# Install wheel in a venv, cd outside the repo, create ./skills/my_skill/, then:
# SkillLoader.load_skill("my_skill")  # should succeed

Type of Change

• Bug Report Fix: Non-breaking change which fixes an execution error or framework bug
• Framework Feature / RFC Updates: Core Framework Update (Changes to loader.py, etc.)

Checklist (all PRs)

• My code follows the Agent Code of Conduct.
• I have run python -m flake8 . and pytest tests/ locally (or the subset relevant to this change).

New or updated skill

Skipped — no new registry skills; only empty __init__.py files for packaging layout.

Constitution & Safety

No skill logic or constitutions changed. Loader behavior is path resolution only; execution semantics unchanged.

Related Issues

Fixes #13