Potential fix for pull request finding 'Duplication in regular expression character class'

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Author: eflumerf

rc/control/bookkeeping.py

@@ -20,7 +20,7 @@
 # ── Precompiled regex patterns (module-level, compiled once at import) ──
 
 _RE_MAX_FRAG_SIZE = re.compile(
-    r"\n[^\n#]*max_fragment_size_bytes\s*:\s*([0-9\.exabcdefABCDEF]+)")
+    r"\n[^\n#]*max_fragment_size_bytes\s*:\s*([0-9\.xabcdefABCDEF]+)")
 _RE_MAX_EVT_SIZE_SEARCH = re.compile(
     r"\n[^\n#]*max_event_size_bytes\s*:\s*[0-9\.e]+")
 _RE_MAX_EVT_SIZE_VALUE = re.compile(