A3S Office v0.67.0

Spreadsheet appearance evidence\n\n- Promoted diagonal borders, linear/path gradients, and native pattern fills into the WPS-informed matrix.\n- Matrix now exposes 52 deterministic ACL contracts and 43 visual contracts across all five editors.\n- Ten new Spreadsheet visual cases passed at desktop and compact layouts.\n- Bounded A3S Test 1.0.1 live session edited and applied a path-gradient boundary, restored grid focus, and reported no page errors.\n- Updated README, bilingual latest docs, release-note data, and CHANGELOG.