VCP visual-synesthesia plugin v2 for DeepSeek Harness (official Slot API): raw-HTML vcp-root cards, streaming render, KaTeX/Mermaid/SVG, builtin fonts

DSH web plugin: Office file previewers (.docx/.xlsx/.pptx) for the better-sidebar editor. Registers the docx/xlsx/pptx file viewers through ctx.betterSidebar.registerFileViewer, keeping the heavy Office render libraries (docx-preview / Univer / SheetJS /