refactor: rename prune-tool.ts to tools.ts to better reflect its contents

Author: Tarquinen

lib/strategies/index.ts

@@ -1,4 +1,4 @@
 export { deduplicate } from "./deduplication"
 export { runOnIdle } from "./on-idle"
-export { createDiscardTool, createExtractTool } from "./prune-tool"
+export { createDiscardTool, createExtractTool } from "./tools"
 export { supersedeWrites } from "./supersede-writes"