chore(corpus): preserve watermark files across updates; document corpus env vars

update.sh now backs up data/corpus_watermark.txt and data/incident_watermark.txt
before git pull and restores them after, mirroring the existing watch.yaml pattern.
Without this, an update would reset watermarks to zero and re-push all corpus
entries from the beginning on the next export run.

.env.example adds a corpus export section documenting the three env vars
needed to opt a node into the Avocet training pipeline.

Closes: #6

.env.example

@@ -23,6 +23,15 @@
 # Remote endpoint to push diagnostic bundles for escalation.
 # TURNSTONE_BUNDLE_ENDPOINT=https://example.com/api/bundles
 
+# --- Log corpus export to Avocet (optional) ---
+# Push ERROR/CRITICAL entries and labeled incidents to the Avocet corpus endpoint
+# for logreading fine-tune training. Requires a consent token issued by CF.
+# Contact alan@circuitforge.tech to register your node and receive a token.
+# Watermarks are stored at data/corpus_watermark.txt and data/incident_watermark.txt.
+# AVOCET_CORPUS_ENDPOINT=https://avocet.circuitforge.tech/api/corpus/log-batch
+# AVOCET_CONSENT_TOKEN=your-uuid-token-here
+# TURNSTONE_SOURCE_HOST=my-server-name   # defaults to system hostname if unset
+
 # --- Periodic batch glean ---
 # Seconds between automatic glean runs from sources.yaml. Set to 0 to disable.
 # TURNSTONE_GLEAN_INTERVAL=900

scripts/update.sh

@@ -6,8 +6,10 @@
 #   sudo bash /opt/turnstone/scripts/update.sh feat/live-watch   # test a branch
 #
 # Local files preserved across updates:
-#   patterns/watch.yaml   — site-specific watch source config
+#   patterns/watch.yaml              — site-specific watch source config
-#   data/                 — database and live journal files (bind-mounted, untouched)
+#   data/corpus_watermark.txt        — corpus export watermark (last exported rowid)
+#   data/incident_watermark.txt      — incident export watermark (last exported timestamp)
+#   data/                            — database and live journal files (bind-mounted, untouched)
 
 set -euo pipefail
 
@@ -21,7 +23,9 @@ echo "==> Turnstone update: branch=$BRANCH"
 
 # ── Preserve site-local config ────────────────────────────────────────────────
 # watch.yaml is tracked in git as a template but overridden per-host.
-# Back it up before the pull and restore it after.
+# Corpus watermarks track the last exported entry/incident — must survive updates
+# or the next export run will re-push everything from the beginning.
+# Back them up before the pull and restore after.
 WATCH_YAML="$REPO_DIR/patterns/watch.yaml"
 WATCH_BACKUP=""
 if [ -f "$WATCH_YAML" ]; then
@@ -29,6 +33,19 @@ if [ -f "$WATCH_YAML" ]; then
   cp "$WATCH_YAML" "$WATCH_BACKUP"
 fi
 
+CORPUS_WM="$REPO_DIR/data/corpus_watermark.txt"
+INCIDENT_WM="$REPO_DIR/data/incident_watermark.txt"
+CORPUS_WM_BACKUP=""
+INCIDENT_WM_BACKUP=""
+if [ -f "$CORPUS_WM" ]; then
+  CORPUS_WM_BACKUP=$(mktemp /tmp/corpus-wm.XXXXXX)
+  cp "$CORPUS_WM" "$CORPUS_WM_BACKUP"
+fi
+if [ -f "$INCIDENT_WM" ]; then
+  INCIDENT_WM_BACKUP=$(mktemp /tmp/incident-wm.XXXXXX)
+  cp "$INCIDENT_WM" "$INCIDENT_WM_BACKUP"
+fi
+
 # ── Pull ──────────────────────────────────────────────────────────────────────
 git fetch --all --tags --quiet
 
@@ -50,6 +67,16 @@ if [ -n "$WATCH_BACKUP" ]; then
   rm -f "$WATCH_BACKUP"
   echo "==> Restored patterns/watch.yaml"
 fi
+if [ -n "$CORPUS_WM_BACKUP" ]; then
+  cp "$CORPUS_WM_BACKUP" "$CORPUS_WM"
+  rm -f "$CORPUS_WM_BACKUP"
+  echo "==> Restored data/corpus_watermark.txt"
+fi
+if [ -n "$INCIDENT_WM_BACKUP" ]; then
+  cp "$INCIDENT_WM_BACKUP" "$INCIDENT_WM"
+  rm -f "$INCIDENT_WM_BACKUP"
+  echo "==> Restored data/incident_watermark.txt"
+fi
 
 # ── Build ─────────────────────────────────────────────────────────────────────
 echo "==> Building $IMAGE ..."