types: document configVersion in BunLockFile (#24641)

packages/bun-types/bun.d.ts

@@ -6430,6 +6430,16 @@ declare module "bun" {
     /** @see https://bun.com/docs/install/catalogs */
     catalogs?: Record<string, Record<string, string>>;
 
+    /**
+     * `0` / `undefined` for projects created before v1.3.2, `1` for projects created after.
+     *
+     * ---
+     * Right now this only changes the default [install linker strategy](https://bun.com/docs/pm/cli/install#isolated-installs):
+     * - With `0`, the linker is hoisted.
+     * - With `1`, the linker is isolated for workspaces and hoisted for single-package projects.
+     */
+    configVersion?: 0 | 1;
+
     /**
      * ```
      * INFO = { prod/dev/optional/peer dependencies, os, cpu, libc (TODO), bin, binDir }