develop
feat(muya): emit preview-image + heading-copy-link events (PG10/PG11) (#4414)
feat(muya): migrate TS rewrite to packages/muya alongside legacy muyajs (#4314)
fix(muya): editor parity with muyajs (themes, fonts, spellcheck) + CLASS_NAMES cleanup (#4454)
refactor(muya): treat the code fence info string as the source of truth (CommonMark) (#4856)
refactor(muya): mark block-tree internals private/protected (#4538)
fix(muya): render <video>/<audio> html blocks instead of the empty placeholder (#4604)