Keep escape parsing linear

Authored-By: Codex (GPT-5) <noreply@openai.com>

check.sh

@@ -40,6 +40,7 @@ VISIBLE_BODY=$(printf '%s\n' "${BODY}" | awk '
 
     visible=""
     pos=1
+    backslash_run=0
     while (pos <= length(line)) {
       if (in_comment) {
         rest=substr(line, pos)
@@ -51,16 +52,11 @@ VISIBLE_BODY=$(printf '%s\n' "${BODY}" | awk '
         visible=visible " "
         pos += comment_end + 2
         in_comment=0
+        backslash_run=0
         continue
       }
 
-      escaped=0
-      escape_pos=pos - 1
-      while (escape_pos >= 1 && substr(line, escape_pos, 1) == "\\") {
-        escaped++
-        escape_pos--
-      }
-      if (substr(line, pos, 1) == "`" && escaped % 2 == 0) {
+      if (substr(line, pos, 1) == "`" && backslash_run % 2 == 0) {
         ticks=1
         while (substr(line, pos + ticks, 1) == "`") ticks++
         close_pos=pos + ticks
@@ -77,6 +73,7 @@ VISIBLE_BODY=$(printf '%s\n' "${BODY}" | awk '
         if (found_close) {
           visible=visible substr(line, pos, close_pos + ticks - pos)
           pos=close_pos + ticks
+          backslash_run=0
           continue
         }
       }
@@ -85,9 +82,13 @@ VISIBLE_BODY=$(printf '%s\n' "${BODY}" | awk '
         visible=visible " "
         in_comment=1
         pos += 4
+        backslash_run=0
         continue
       }
-      visible=visible substr(line, pos, 1)
+      char=substr(line, pos, 1)
+      visible=visible char
+      if (char == "\\") backslash_run++
+      else backslash_run=0
       pos++
     }
     print visible