Show whiteboard viewers

[carlassmann]

What changed

• add asset-scoped Jazz session presence for open whiteboards
• show a visible, accessible viewer count in the whiteboard header
• count the same account on another device/session while excluding the current session
• expire abruptly closed sessions automatically and support existing whiteboards lazily
• add English and German labels plus presence-count tests

Why

Concurrent whiteboard editors can overwrite each other's saved revisions. Showing who else has the board open gives users an immediate warning before editing or saving.

Validation

• bun run check:types
• focused whiteboard tests: 9 passed
• full suite: 709 passed initially; 3 load-related timing failures all passed on isolated rerun (27/27)
• targeted ESLint and Prettier checks
• agent-browser QA with two anonymous tabs sharing one identity: both showed 1 other viewing

Browser QA also exposed a heartbeat render loop in the initial implementation; the final lifecycle loads the feed once per editor session and remains responsive.

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
alkalye	Ready	Preview	Aug 19, 2026 12:24pm