Critical bug fix for v3.1.6 and glz::json_t

Recursive depth counting was added in v3.1.6 (#1202) to prevent stack overflows from deep recursive JSON inputs parsing into glz::json_t (this would typically only be encountered as an nefarious attack). This fixes a bug that missed counting object closures.
by @stephenberry in #1216

Other Fixes

• Added missing check for surrogate unicode pair parsing by @stephenberry in #1214

Full Changelog: v3.1.6...v3.1.7