Split forwards return docstring into two seperate @returns for each point of failure.

Author: SharafMohamed

src/log_surgeon/finite_automata/RegexNFA.hpp

@@ -152,8 +152,10 @@ class RegexNFAState {
     /**
      * @param state_ids A map of states to their unique identifiers.
      * @return A string representation of the NFA state on success.
-     * @return Forwards `PositiveTaggedTransition::serialize`'s or
-     * `NegativeTaggedTransition::serialize`'s return value (std::nullopt) on failure.
+     * @return Forwards `PositiveTaggedTransition::serialize`'s return value (std::nullopt) on
+     * failure.
+     * @return Forwards `NegativeTaggedTransition::serialize`'s return value (std::nullopt) on
+     * failure.
      */
     [[nodiscard]] auto serialize(
             std::unordered_map<RegexNFAByteState const*, uint32_t> const& state_ids