feat: in-text citations — visual styling, per-unit splitting, ADS search fallback

fix: close pymupdf doc in extract_equations; guard short anchor snippets; use grid layout for equation tag

feat: equation rendering — heuristic detector, PNG clip, anchor to paragraph, Reader display

feat: reader notes — margin note cards, notebook drawer, paper-level note, export

feat: in-text citations — splitCitations, cite spans, slim ref popover, muted styling

fix: parser fidelity — pending buffer, refs capture, heading chain, hygiene, caption gate, length basis

feat: retrieved-works preference, text input, beacon rename

fix: scrollable popovers; default annotation mode is historical context

feat: figure mention popovers with caption annotator

fix: restore screen flex centering; skip button only when result ready

feat: upload and pipeline screens wired to real backend

feat: scaffold Vite frontend with ported prototype CSS