feat: add required mode flag to cleanup and close

- Made `mode` a mandatory property in `MultiModelOptions`, `CloseSessionOptions`, and `CleanupOptions`.
- Updated function signatures to accept `mode` and removed default empty option objects where appropriate.
- Passed `mode: "cli"` from CLI commands and `mode: "tool"` from tool commands to cleanup, close, and open operations.
- Adjusted internal handling to use the provided `mode` (removed fallback defaults).
- Updated type definitions and added documentation for the new `mode` field.

src/tools/cleanup.ts

@@ -31,6 +31,7 @@ Arguments:
     const result = await cleanupMultiModel({
       force: true,
       remote: args.noRemote ? false : args.remote,
+      mode: "tool",
     });
 
     if (!result.success) {