feat(ux): dedupe page links and collapse tree row actions behind an overflow menu

[alexk-dev]

Summary

Fixes two reported defects and the mobile-first issues a UX audit surfaced around them.

Duplicated links at the bottom of a document. The cause was data, not a double render: extractResolvedLinks emitted one entry per link occurrence, so a body referencing the same page twice produced two identical rows under Outgoing links, and two identical Backlinks rows on the target page. The React keys collided as well. Deduped by resolved target path in WikiApplicationService, plus a defensive pass in LinkInfo so the pane stays correct against an older backend.

Tree navigation on desktop. Every row rendered up to seven icon buttons on hover. Moving the pointer onto a row materialised ~214px of controls, re-truncating the title under the cursor, with Delete adjacent to Convert. Replaced with a single overflow menu (Radix DropdownMenu) at all breakpoints; the trigger keeps its slot reserved so revealing it causes no reflow.

Worth calling out: the old max-md:hidden guard on that cluster never won the cascade — (0,1,0) against group-hover:flex at (0,2,0), and media queries add no specificity. Tapping a row on mobile focused the title button, matched :focus-within, and revealed all seven desktop icons plus the mobile overflow button — eight controls in a ≤320px sidebar, collapsing the title to zero width.

Also fixed

Area	Change
Sidebar	Search tab opened the embedded panel and the modal dialog on top of it; now swaps the panel in place
Editor	Unsaved-changes and conflict prompts were bare overlay divs with no focus trap, Escape or dialog role; now use ModalCard. Hotkeys no longer fire from behind an open prompt
iOS zoom	Form fields (14px) and the code editor (13px) triggered Safari auto-zoom on focus; both render at 16px on phones
Editor	Autofocus gated behind (pointer: fine) so the on-screen keyboard no longer covers the fixed save bar
Markdown	Wide tables dragged the whole article sideways; each table now scrolls in its own container
Touch targets	44px minimum across tree rows, editor toolbar, links pane, history actions and modal dismiss
Assets	Rows overflowed the dialog on a phone and the rename field was a fixed 160px in a ~263px box; rows wrap and rename gets its own line plus a cancel action
Layout	sidebarVisible was seeded once at module load and went stale on rotation; now follows breakpoint crossings while preserving manual toggles
Chat	Sends on Enter, Shift+Enter for a newline, transcript exposed as a live region
Users	Deletion used window.confirm; now uses the same in-app dialog as every other destructive action
a11y	aria-expanded/aria-controls on the sidebar toggle, tab/tabpanel semantics, aria-current on the active tree row