fix: use real BusyBox crontab instead of mock for cron verification (#668)

The mock crontab file was not being created despite PATH precedence
working correctly. Replace the mock with the real BusyBox crontab
already available in the Forgejo Alpine image. Verify cron entries
via 'crontab -l' output instead of checking a mock state file.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/smoke-init.sh

@@ -194,20 +194,11 @@ chmod +x "$MOCK_BIN/claude"
 printf '#!/usr/bin/env bash\nexit 0\n' > "$MOCK_BIN/tmux"
 chmod +x "$MOCK_BIN/tmux"
 
-# ── Mock: crontab ──
-cat > "$MOCK_BIN/crontab" << 'CRONMOCK'
-#!/usr/bin/env bash
-CRON_FILE="/tmp/smoke-mock-state/crontab-entries"
-case "${1:-}" in
-  -l) cat "$CRON_FILE" 2>/dev/null || true ;;
-  -)  cat > "$CRON_FILE" ;;
-  *)  exit 0 ;;
-esac
-CRONMOCK
-chmod +x "$MOCK_BIN/crontab"
+# No crontab mock — use real BusyBox crontab (available in the Forgejo
+# Alpine image). Cron entries are verified via 'crontab -l' in step 6.
 
 export PATH="$MOCK_BIN:$PATH"
-pass "Mock binaries installed (docker, claude, tmux, crontab)"
+pass "Mock binaries installed (docker, claude, tmux)"
 
 # ── 3. Run disinto init ─────────────────────────────────────────────────────
 echo "=== 3/6 Running disinto init ==="
@@ -338,25 +329,25 @@ fi
 
 # ── 6. Verify cron setup ────────────────────────────────────────────────────
 echo "=== 6/6 Verifying cron setup ==="
-cron_file="$MOCK_STATE/crontab-entries"
-if [ -f "$cron_file" ]; then
-  if grep -q 'dev-poll.sh' "$cron_file"; then
+cron_output=$(crontab -l 2>/dev/null) || cron_output=""
+if [ -n "$cron_output" ]; then
+  if printf '%s' "$cron_output" | grep -q 'dev-poll.sh'; then
     pass "Cron includes dev-poll entry"
   else
     fail "Cron missing dev-poll entry"
   fi
-  if grep -q 'review-poll.sh' "$cron_file"; then
+  if printf '%s' "$cron_output" | grep -q 'review-poll.sh'; then
     pass "Cron includes review-poll entry"
   else
     fail "Cron missing review-poll entry"
   fi
-  if grep -q 'gardener-run.sh' "$cron_file"; then
+  if printf '%s' "$cron_output" | grep -q 'gardener-run.sh'; then
     pass "Cron includes gardener entry"
   else
     fail "Cron missing gardener entry"
   fi
 else
-  fail "No cron entries captured (mock crontab file missing)"
+  fail "No cron entries found (crontab -l returned empty)"
 fi
 
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