docs: pre-push PII guard + scrub conventions

main history was rewritten once to scrub a leaked work email. Document a
pre-push email guard (grep with a synthetic-domain allowlist; empty = clean) in
AGENTS.md and reference it from CLAUDE.md, plus the post-scrub conventions: no
real personal/work emails (use @example.com), the only real address allowed is
the maintainer contact caseywitt@proton.me, generic personas (admin/alice/sam),
party name Acme. Never push pre-scrub history or stale tags.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

AGENTS.md

@@ -227,6 +227,20 @@ Format: `trackingNumber_revision (status) - title.extension`
 - Hand-edited website content lives in a separate Codeberg repo (`codeberg.org/VARASYS/ZDDC-website`, cloned at `~/src/zddc-website/`). Source-code commits go to `main` here; content commits go to that repo
 - Release artifacts live on the deploy host (`/srv/zddc/`), not in any git history. Use `./deploy` to publish
 
+### Pre-push PII guard (run before EVERY push)
+
+`main` was rewritten once to scrub a leaked work email (history reset to a single clean commit; all old tags deleted; versioning rebootstrapped at `v0.0.26`). A leaked address persists in **history + tags**, not just files — so it must never re-enter. Before any push:
+
+```sh
+# Flags any email NOT a known synthetic placeholder or the maintainer contact.
+git grep -InE '[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}' \
+  | grep -viE '@example\.(com|org|io|net)|caseywitt@proton\.me|@(my|your)company\.com|@(partner|acme|beta|vendor|evil|x|company|host|admin|anywhere|other)\.(com|org)|@regulator\.gov|@(zddc\.)?varasys\.io|@bitnest\.cc|@proton\.me|@nhn\.com|@ex\.io'
+```
+
+- **Empty output = clean.** Any line is a STOP: confirm it's a synthetic placeholder; if it's a real personal/work address, replace it with an `@example.com` placeholder before pushing (and extend the allowlist above only for genuinely-synthetic example domains).
+- **Conventions** (the scrub genericized everything): no real personal/work emails — use `@example.com`. The only real address allowed anywhere is the maintainer contact **`caseywitt@proton.me`** (`SECURITY.md` + as the git commit author). Generic personas only — `admin` / `alice` / `sam`; party name **Acme**.
+- **Never** push a branch still carrying pre-scrub history, and **never** push stale local tags (the old 165 are gone; `zddc-server-vX.Y.Z` triggers the release+deploy pipeline).
+
 ### Releasing — lockstep stable + beta snapshot
 
 **Lockstep convention.** Every stable cut bumps all 8 artifacts (7 HTML tools + zddc-server) to the same version, even if a tool didn't change. Per-tool independent versions are gone. The coordinated next-stable target is `max(latest tag across all 8 tools) + 1` — `_coordinated_next_stable` in `shared/build-lib.sh`.

CLAUDE.md

@@ -7,6 +7,7 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 - **Commit freely** — make commits as appropriate for the work being performed. Each commit should be a coherent, reviewable unit (no WIP/checkpoint noise). The default rule "never commit without explicit ask" does NOT apply in this repo.
 - **Push only when explicitly told** — `git push` requires a fresh request from the user every time. Approval to commit does not carry forward to push, and approval to push once does not carry forward to a later push.
 - **No squashing on push** — keep granular history. Each commit should already be meaningful (per the rule above), so squashing erases useful detail rather than removing noise. Multi-commit branches with a clean history are preferred over force-pushed squash-merges.
+- **Pre-push PII guard — run before EVERY push.** `main` history was rewritten once to scrub a leaked work email; a leak persists in history + tags, not just files. Before any push, run the guard in AGENTS.md ("Pre-push PII guard"). No real personal/work emails: use `@example.com` in examples; the only real address allowed is the maintainer contact `caseywitt@proton.me` (SECURITY.md + as commit author). Generic personas only (admin / alice / sam); party name **Acme**. Never push stale local tags, and never push a branch still carrying pre-scrub history.
 
 ## Authoritative docs — read these first