fix(verify-harvard): skip doc-comment lines + add word-boundary guards

The grep -iE 'If|...|For|...' was case-insensitively matching the English
word "for" in doc-comment prose ("for shortest path", "algebraic form")
inside the DataExpr enum block, producing false positives for the semiring
operators Min/Max/Or/Xor — all of which are genuinely data-level.

Fix: filter comment lines with `grep -v '^\s*//'` before the variant scan,
and wrap each keyword in `\b...\b` so e.g. "form" no longer matches "For".

`just contractile-check` now passes: bust-check ✓.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: hyperpolymath

Justfile

@@ -486,7 +486,7 @@ verify-harvard:
     if [ -f "$AST_FILE" ]; then
         DATA_ENUM=$(sed -n '/enum DataExpr/,/^}/p' "$AST_FILE" 2>/dev/null || true)
         if [ -n "$DATA_ENUM" ]; then
-            CONTROL_IN_DATA=$(echo "$DATA_ENUM" | grep -iE 'If|Match|Loop|While|For|Branch|Send|Receive|Spawn|Choose|Offer' || true)
+            CONTROL_IN_DATA=$(echo "$DATA_ENUM" | grep -v '^\s*//' | grep -iE '\b(If|Match|Loop|While|For|Branch|Send|Receive|Spawn|Choose|Offer)\b' || true)
             if [ -n "$CONTROL_IN_DATA" ]; then
                 echo "  FAIL: DataExpr enum contains control-flow variants:"
                 echo "$CONTROL_IN_DATA" | sed 's/^/    /'