add publish-pip skill for manual PyPI releases

Encoded runbook for the manual (no-CI, no-tag) PyPI release flow:
version bump in pyproject.toml, .venv build + twine upload, and the
local gotchas hit during the 0.6.6 publish (build/twine absent from a
fresh venv, the 'import build' false positive, SSL_CERT_FILE=certifi
for PyPI API verification, clean dist before upload, verify the built
wheel version before the permanent upload).

Co-Authored-By: Claude <noreply@anthropic.com>

Author: HumanBean17

.agents/skills/publish-pip/SKILL.md

@@ -0,0 +1,107 @@
+---
+name: publish-pip
+description: Use when the user asks to publish or release the java-codebase-rag pip package to PyPI, bump + publish a new version, or cut a PyPI release. Also use when a manual publish is failing on missing build/twine tooling or an SSL verification error.
+disable-model-invocation: true
+---
+
+# Publish Pip Package
+
+Manual, from-worktree release of `java-codebase-rag` to PyPI. There is **no CI
+release and no git tag** — the version lives only in `pyproject.toml`, and
+releases are built + uploaded with the venv `build` / `twine` tools. PyPI uploads
+are **permanent**: a version can be yanked but never overwritten, so verify the
+version *before* uploading.
+
+## When to use
+
+- user says "publish/release the package", "bump version and publish",
+  "cut a PyPI release"
+- a prior publish failed partway (tool missing, SSL error, wrong version)
+
+Do **not** use this for installing dev deps (`pip install -e ".[dev]"`) or for
+adding a runtime dependency to `pyproject.toml`.
+
+## Prerequisites
+
+- `.venv` at repo root. Use **only** `.venv/bin/python`, `.venv/bin/pip`,
+  `.venv/bin/twine` — the system Python shadows the venv CLI.
+- `~/.pypirc` present with the PyPI upload token. Never print it; twine reads it
+  automatically.
+
+## Workflow
+
+1. **Bump version** — the single source is `pyproject.toml` (`version = "X.Y.Z"`,
+   near line 7). Read the current value, increment per request (patch = `Z+1`).
+2. **Ensure tooling** — `build` and `twine` are not runtime deps and may be
+   absent from a fresh worktree venv:
+   ```bash
+   .venv/bin/python -m build --version   # real PyPA build, else "No module named build"
+   .venv/bin/twine --version
+   .venv/bin/pip install build twine      # if either is missing
+   ```
+   ⚠️ Don't use `import build` to confirm the tool — it can succeed by resolving
+   to a local `build/` namespace dir or a stale install even when the PyPA tool
+   is absent. Always check via `-m build --version`.
+3. **Clean old artifacts** — re-uploading an existing PyPI version is rejected,
+   and you must never mix stale files into `dist/`:
+   ```bash
+   rm -rf dist build *.egg-info
+   ```
+4. **Build** sdist + wheel:
+   ```bash
+   .venv/bin/python -m build
+   ```
+   Expect `dist/java_codebase_rag-<ver>-py3-none-any.whl` and `.tar.gz`.
+5. **Verify the built version** before upload (catches a forgotten bump):
+   ```bash
+   .venv/bin/python -c "import zipfile,glob; w=glob.glob('dist/*.whl')[0]; z=zipfile.ZipFile(w); m=[n for n in z.namelist() if n.endswith('METADATA')][0]; print([l for l in z.read(m).decode().splitlines() if l.startswith('Version')][0])"
+   ```
+6. **Upload** (permanent — confirm the version is right first):
+   ```bash
+   .venv/bin/twine upload dist/*
+   ```
+   twine prints the live URL on success:
+   `https://pypi.org/project/java-codebase-rag/<ver>/`.
+7. **Verify on PyPI** via the JSON API. ⚠️ Python's `urllib`/`requests` SSL
+   verification fails locally (missing CA bundle) — set `SSL_CERT_FILE`:
+   ```bash
+   CERT=$(.venv/bin/python -c "import certifi; print(certifi.where())")
+   SSL_CERT_FILE="$CERT" .venv/bin/python -c "import urllib.request,json; d=json.load(urllib.request.urlopen('https://pypi.org/pypi/java-codebase-rag/json')); print('latest:', d['info']['version'])"
+   ```
+8. **Commit + push the version bump** so the repo matches what was published
+   (commit convention: `bump version to X.Y.Z`). `dist/`, `build/`, and
+   `*.egg-info` are gitignored — do not commit them.
+
+## Quick reference
+
+| Step | Command |
+|------|---------|
+| Bump | edit `pyproject.toml` `version` |
+| Tooling | `.venv/bin/pip install build twine` |
+| Clean | `rm -rf dist build *.egg-info` |
+| Build | `.venv/bin/python -m build` |
+| Verify wheel | read `Version:` from `dist/*.whl` METADATA |
+| Upload | `.venv/bin/twine upload dist/*` |
+| Verify live | `SSL_CERT_FILE="$(.venv/bin/python -m certifi)"` + pypi JSON API |
+| Commit | `bump version to X.Y.Z` |
+
+## Common mistakes
+
+- **Re-uploading an existing version** → PyPI returns 400. Bump first; clean `dist/`.
+- **`import build` succeeds but `python -m build` fails** → `import` resolved to
+  a local `build/` namespace dir or stale module, not the PyPA tool. `pip install
+  build`, then confirm with `-m build --version`.
+- **PyPI verification SSL error** (`CERTIFICATE_VERIFY_FAILED`) →
+  `SSL_CERT_FILE=$(.venv/bin/python -c "import certifi;print(certifi.where())")`.
+- **Forgot to bump / uploaded the wrong version** → permanent. Always run the
+  METADATA version check (step 5) before `twine upload`.
+- **Used system `python` / `twine`** → wrong env / missing credentials. Always
+  `.venv/bin/`.
+- **Left the version bump uncommitted** → repo drifts from PyPI. Commit + push.
+
+## Notes
+
+- Release `0.6.6` (erase fix, PR #348) established this runbook; the gotchas
+  above were all hit for real during that publish.
+- If you publish from an unmerged feature branch, PyPI will be ahead of `master`
+  until the branch merges — call that out.