I vote to blow up all stars in around SOL, so that 100Ly void bubble is created around it and our home system is safe.
We could have a CG to bring in as many tons of TNT as possible, so it can be later thrown into stars for explosive purposes.
And don't worry, we'll still be able to fly to Sol using FSD boost for 50Ly+ spaceships. Thargoids though - not so much. They can't engineer.
Check-mate, bugs!
Previous lore has it that Thargoid drives could do much larger jumps than ours, possibly hundreds of Ly per jump. You may need to expand your plans to destroying the whole bubble, to prevent the Thargoids getting to Earth.
On a more general level, why the special concern for Earth? What real significance has it, really, compared with the many other high pop systems? In a full scale war between Humans and Thargiods, taking out one system is not significant, regardless of it's history. It not like any serious power is going to let itself be vulnerable as to be taken out when a single location is hit.