fix(security): complete eval removal for stdin-form runner

Previous commit added the PARSER_CMD array but left the two
`if eval "${PARSER}" < "$f"` lines untouched — the awk patcher's
regex only matched the argument form, not the stdin form. That left
the script referring to a $PARSER binding that no longer existed.
Replace them with "${PARSER_CMD[@]}" < "$f". Restore exec bit.

Note: verification/conformance/run_conformance.sh is a symlink to
../conformance/run_conformance.sh, so patching the real path here
also fixes the verification/ view automatically.

Resolves 2 Critical panic-attack CommandInjection findings.

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

Author: hyperpolymath

conformance/run_conformance.sh

@@ -28,7 +28,7 @@ TOTAL=0
 for f in "${SCRIPT_DIR}"/valid/*.bet; do
     TOTAL=$((TOTAL + 1))
     name="$(basename "$f")"
-    if eval "${PARSER}" < "$f" >/dev/null 2>&1; then
+    if "${PARSER_CMD[@]}" < "$f" >/dev/null 2>&1; then
         echo "  PASS  valid/${name}"
         PASS=$((PASS + 1))
     else
@@ -41,7 +41,7 @@ done
 for f in "${SCRIPT_DIR}"/invalid/*.bet; do
     TOTAL=$((TOTAL + 1))
     name="$(basename "$f")"
-    if eval "${PARSER}" < "$f" >/dev/null 2>&1; then
+    if "${PARSER_CMD[@]}" < "$f" >/dev/null 2>&1; then
         echo "  FAIL  invalid/${name}  (expected failure, got success)"
         FAIL=$((FAIL + 1))
     else