Adds a small auto-dismissing pill notification at the bottom-center of the participants area: 'Settings saved' on Apply Changes, 'Transcoder topology applied — restart Teams to take effect' after the one-click NDI groups setup. ToastViewModel owns its own DispatcherTimer and resets the dismissal countdown on successive calls, so the most recent message is always the one visible. Hooked into MainViewModel and threaded into GlobalSettingsViewModel via constructor injection.
_NEXT.md rewritten to reflect the May 2026 hardening pass: separates engine / UI / networking / Phase E.1 / diagnostics / CI / tests sections, lists every shipped item, and re-prioritizes the remaining work (Phase E.2-E.3 embedded Teams, code-signing the MSI, refresh-discovery affordance, output thumbnail previews, settings panel UX, auto-disable on departure, operator presets).
First step of Phase E.1 from the new spec at docs/superpowers/specs/2026-05-08-embedded-teams-orchestration.md: a third icon in the left rail launches the Microsoft Teams desktop client as a subprocess of TeamsISO so the operator doesn't have to leave the app to start a meeting.
Services/TeamsLauncher tries the ms-teams: URI first, falls back to %LOCALAPPDATA%\\Microsoft\\WindowsApps\\ms-teams.exe (new Teams), then the classic Update.exe handoff. On failure surfaces a friendly MessageBox with the install link.
The spec doc lays out the full three-phase roadmap (launcher -> window orchestration -> in-app meeting controls via Graph API or UIAutomation) and explicitly calls out what's out of scope (replacing Teams' media stack).
_NEXT.md updated to mark Phase D done and queue Phase E + remaining polish items (code-signing, Inter/JetBrains Mono font bundling, real Wild Dragon dragon-mark, drops counter, running-fps display).
