feat(docker): add ZERO_AUTO_RESET configuration for improved replication safety

- Introduced the ZERO_AUTO_RESET environment variable to enable automatic reset of the SQLite replica in case of replication halts.
- Updated Docker Compose files to include ZERO_AUTO_RESET in service configurations.
- Enhanced documentation to clarify the purpose and usage of the new variable.

surfsense_backend/scripts/docker/entrypoint.sh

@@ -49,10 +49,10 @@ trap cleanup SIGTERM SIGINT
 # ── Database migrations (only for migrate / all) ─────────────
 # Fail-fast contract:
 #   - alembic upgrade head must succeed within ${MIGRATION_TIMEOUT:-900}s
-#   - zero_publication must exist in pg_publication afterwards
+#   - zero_publication must match the canonical app.zero_publication shape
 # Either failure exits non-zero so the dedicated `migrations` compose
 # service exits non-zero, halting the rest of the stack instead of
-# silently producing a half-built system that crash-loops zero-cache.
+# silently producing a drifted Zero publication.
 run_migrations() {
     echo "Running database migrations..."
     for i in {1..30}; do
@@ -73,58 +73,13 @@ run_migrations() {
     fi
     echo "Migrations completed successfully."
 
-    echo "Verifying zero_publication exists in Postgres..."
-    local pub_oid
-    pub_oid=$(python <<'PY' 2>/dev/null || true
-import asyncio
-import sys
-from sqlalchemy import text
-from app.db import engine
-
-
-async def get_oid():
-    async with engine.connect() as conn:
-        result = await conn.execute(
-            text("SELECT oid FROM pg_publication WHERE pubname = 'zero_publication'")
-        )
-        row = result.first()
-        if row is None:
-            sys.exit(1)
-        print(int(row[0]))
-
-
-asyncio.run(get_oid())
-PY
-)
-    if [ -z "${pub_oid}" ]; then
-        echo "ERROR: zero_publication is missing from Postgres after running alembic." >&2
-        echo "This usually means migration 116 (or a later publication migration) did not run." >&2
+    echo "Verifying zero_publication matches the canonical shape..."
+    if ! python -m app.zero_publication --verify; then
+        echo "ERROR: zero_publication does not match the canonical shape." >&2
         echo "Inspect alembic state with:" >&2
         echo "  docker compose exec db psql -U \"\$DB_USER\" -d \"\$DB_NAME\" -c 'SELECT * FROM alembic_version;'" >&2
         exit 1
     fi
-    echo "zero_publication verified (oid=${pub_oid})."
-
-    # Stale-replica safety net: if /zero-init is mounted (i.e. we are the
-    # dedicated `migrations` compose service), drop a marker file when the
-    # publication oid changed (or on first run) so the wrapped zero-cache
-    # entrypoint can wipe /data/zero.db before starting. This recovers from
-    # the case where a previous zero-cache crashed mid-init and left a
-    # half-built SQLite replica without a `_zero.tableMetadata` table.
-    if [ -d /zero-init ]; then
-        local stored_oid=""
-        [ -f /zero-init/last_pub_oid ] && stored_oid=$(cat /zero-init/last_pub_oid 2>/dev/null || true)
-        if [ -z "${stored_oid}" ] || [ "${stored_oid}" != "${pub_oid}" ]; then
-            echo "Publication oid changed (stored=${stored_oid:-<none>}, current=${pub_oid}); writing /zero-init/needs_reset."
-            : > /zero-init/needs_reset
-            chmod 666 /zero-init/needs_reset 2>/dev/null || true
-        fi
-        echo "${pub_oid}" > /zero-init/last_pub_oid
-        chmod 666 /zero-init/last_pub_oid 2>/dev/null || true
-        # World-writable dir so the (possibly non-root) zero-cache container
-        # can `rm -f /zero-init/needs_reset` after acting on the marker.
-        chmod 777 /zero-init 2>/dev/null || true
-    fi
 }
 
 # ── Service starters ─────────────────────────────────────────