Smaller fixes and improvements across the platform

Fixed

• Stale session links no longer show repeated errors A shared link to a session that no longer exists now clears itself from the address bar — so the "session not found" message stops reappearing on every reload. If another session is already open, the link updates to point to that one instead.
• Failed filter reset shows a helpful message When resetting filters failed, a raw technical error was shown instead of a clear explanation. You now see a message that tells you what to do next.
• Refine Search fields are easier to navigate Every field in the Refine Search dialog now has a proper label for screen readers, and clicking a field's caption focuses it — making the dialog easier to use with assistive technology.