decodeHtmlEntities only handled decimal numeric character references
(é); the equally valid hexadecimal form (é) fell through
undecoded and surfaced as raw text in titles, companies, locations and
descriptions. It also used String.fromCharCode, which corrupts
supplementary-plane code points (e.g. emoji, U+1F600).
Add a hexadecimal numeric-entity rule and route both decimal and hex
through a fromCodePoint-based helper with a valid-range guard. Add
network-free unit tests covering hex, uppercase-X hex, decimal
(regression) and astral code points via the exported parse functions.
