The map's share card resolves under 100 ms: /og/map/trevato~forge.png and its SVG draw what is open #6150

Measured on 2026-10-26: /og/map/trevato~forge.png took 1.8 s on the server (resolve;dur=1164, raster;dur=609). The SVG is 1.9 MB, because it draws all 2,300 issues. Every share of the map link pays this cost once per cache window.

Done when:

• [ ] The map card draws open issues only and names the done count in its caption. If #6121 has already changed the card to match, say so and close this as done.
• [ ] A test with 2,000 closed and 300 open issues asserts that the card's SVG is under 200 KB and its resolve step is under 100 ms.

Files: src/web/og (the map card), test/og-map.test.ts. Risk: #6121 changes the page's default in src/web/pages/map.ts. Keep this change in src/web/og.