Discord Preview and QoL fixes.

Discord Link Previews

• Pasting a room, lobby, or shared setup link into Discord (or Slack, iMessage, and similar) now unfurls into a real preview card instead of a bare URL.
• Room previews show the game name, who is hosting, when it started, and how many seats are actually open.
• Shared setup links now describe the table being offered rather than showing nothing.
• Link previews use the project's artwork, preferring the wide backdrop because it fills a link card properly where a small logo gets demoted to a thumbnail.

Dextrous Sync

• Fixed: re-syncing a rebuilt deck left the old cards sitting alongside the new ones, showing as duplicate names with different quantities that no further sync could clear.
• Components removed by a sync are now cleared from the table, including cards inside decks, stacks, and your hand. Previously they stayed behind pointing at something that no longer existed.

Playtest Room

• Drawn cards, tokens, and bag items now come off upright from your own point of view, no matter which way the deck or the table is turned.
• Added a player option, "Draw in deck's rotation", off by default, for anyone who wants the old behaviour where a drawn piece matches the deck it came from.
• The drawing tool now shows a marker cursor tinted with your current pen colour instead of a crosshair. The eraser keeps the crosshair.

Deploy Screen

• The "Deploying a New Version" screen was rebuiltand will now refreshes itself every 15 seconds so you no longer have to reload manually.