Whiteboard 0.5.2

-- First of all, sorry about popping the toast and the update badge, its fixed in this version!

Animations: tours, clips and previews (experimental, off by default)

• An animation whose frames carry code gets a tour: Expand becomes Tour, and the panel and frames move together (#1483).
• Animations paint in as they stream instead of popping in (#1483).
• New clip block: one continuous timeline you play, pause and jump around by markers (#1483).
• Scene cards can take a form (window, bars, cylinder…), an outline and a colour, so a database reads differently from a service (#1498, #1508).
• Animations fit the board's reading width, with at least 720px of stage, and link labels avoid other lines (#1507).
• Agents can render a frame of the animation they wrote with session_render and see it, instead of driving the screen (#1501).
• Animations setting now reaches agents on remote hosts (#1495).

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New

• ⌘K (Ctrl+K elsewhere) jumps to any board, PR or command; paste a GitHub PR link to open or create its board (#1493)
• A board keeps one share link: resharing updates it in place, and receivers' copies refresh (#1477, #1527)
• Sidebar has an Unread section; right-click or multi-select rows to mark as read (#1520)
• Share boards that live on a remote host (#1480)
• Boards on a live worktree can be shared as frozen, view-only snapshots; uncommitted code opens in the browser only (#1487)
• Open files in IntelliJ IDEA at the selected line (#1514, fixes #1510 from @faysou)
• Home rows show a remote board's host (#1526)
• The Release notes tab lists every release and scrolls to the one you updated to (#1486)
• Developer option review.serviceUrl points sign-in and sharing at another service, such as staging (#1484)

Changed

• Updates are announced only by the rex-inspired bottom-right pill. The "ready to install" and "available" toasts and the review.update.showPill setting are gone, and dismissing the pill hides that update in every window and
  across relaunches, if this is too annoying let us know lol (#1529)
• Share errors say what went wrong (blocked, size or rate limit, service down, update required) instead of a generic login error (#1482)
• Source tree is hidden on shared and hosted boards, which have no checkout (#1485, #1494)
• Updated Electron to 43.8.6 for Chromium security fixes (#1491)
• Shared boards open in newer Desktops even when a later version adds fields, and share peeks on new code are painted as diffs (#1470)

Fixed

• On Windows and Linux, a tour's close button and the board's page-bar buttons sat under the window controls (#1513, fixes #1490 from @batudez)
• Remote boards didn't save typing, lost their header crumb, repository and PR state, and never resolved links; session_get, history, lenses and render failed for local agents (#1524)
• A hand-made animation node lost its own position when it took a form (#1508)
• Release notes showed <!-- whiteboard:show-notes --> as text (#1481)

Full Changelog: v0.5.1...v0.5.2