feat(desktop): show the installed app's own version in the UI

Nothing displayed which desktop build was actually installed — debugging
a stuck update meant inferring the current version backwards from the
update prompt's target version. Added DesktopVersionBadge (next to the
existing server-side VersionBadge) using @tauri-apps/api's getVersion(),
the real running app version baked in from tauri.conf.json. No-ops in a
browser. Exported inTauri() from origin.ts instead of redefining it again.

wiki/log.md

@@ -2808,3 +2808,12 @@ and fixed a real, pre-existing Komodo ResourceSync misconfig (resource-sync-park
 `dev`, not `stage`, silently reading resources.toml from the wrong branch for months with zero
 effect until dev/stage first diverged today) — full writeup on [[fleet-deployment-komodo]], which
 had already warned about exactly this gotcha back in 2026-07-07 and it happened anyway.
+
+## [2026-09-03] feat | Desktop app version now visible in the UI (was invisible)
+
+There was no way to see which desktop build was actually installed anywhere in the app — an
+operator debugging a stuck update had to infer it backwards from the update prompt's target
+version ("it's offering v0.1.4, so I must be on v0.1.3"). Added DesktopVersionBadge next to the
+existing server-side VersionBadge in router.tsx, using @tauri-apps/api's getVersion() (the real
+running app version, synced to the git tag at build time by release.yml). No-ops in a browser.
+Full detail on [[desktop-shell-tauri]].