fix: reset checkAuth debounce in linkShareAuth to prevent redirect loop

When a logged-in user opens a public link share, the 1-minute debounce
on checkAuth() caused it to skip re-parsing the new link share JWT.
This left authLinkShare as false, triggering an infinite redirect loop
in the router guard.

Fixes #2546

frontend/src/stores/auth.ts

@@ -283,6 +283,9 @@ export const useAuthStore = defineStore('auth', () => {
 			password: password,
 		})
 		saveToken(response.data.token, false)
+		// Reset the debounce so checkAuth() actually parses the new link share
+		// JWT instead of silently returning due to the 1-minute throttle.
+		lastUserInfoRefresh.value = null
 		await checkAuth()
 		return response.data
 	}