fix: ignore markdown emphasis when matching read answers

The read checker matched a task's required-fact phrasings as plain
substrings of the agent's report after only lowercasing and collapsing
whitespace. An answer that was substantively correct but wrapped a value in
markdown (e.g. `**5**`) failed the match, because the emphasis markers broke
the phrase adjacency (`**5** open` does not contain `5 open`) — a correct
answer scored incorrect on formatting alone.

Strip markdown emphasis/code markers (`*`, `_`, backtick) during
normalization so the match is on substance, not presentation. A guard test
confirms a wrong value still fails after stripping.

bench/checker.ts

@@ -253,9 +253,18 @@ export function checkReadAnswer(facts: RequiredFact[], report: string): CheckRes
   };
 }
 
-/** Lower-case and collapse runs of whitespace so incidental phrasing does not matter. */
+/**
+ * Lower-case, drop markdown emphasis/code markers, and collapse runs of
+ * whitespace so incidental phrasing and formatting do not matter — a report that
+ * bolds a value (`**5**`) matches a phrasing that does not (`5 open`), since the
+ * emphasis is presentation, not substance.
+ */
 function normalizeText(text: string): string {
-  return text.toLowerCase().replace(/\s+/g, " ").trim();
+  return text
+    .toLowerCase()
+    .replace(/[*_`]/g, "")
+    .replace(/\s+/g, " ")
+    .trim();
 }
 
 /**