Summary

Add an "Effective mounts" section to openclaw sandbox explain so users can quickly see the sandbox file-system exposure (workspace/agent mounts + docker binds).

Changes

• JSON: add sandbox.mounts: Array<{ source, hostRoot, containerRoot, writable }>
• Text output: print Effective mounts: after Effective sandbox:
• Deterministic order: workspace → agent → bind

Acceptance criteria

• pnpm -s openclaw sandbox explain shows the new section
• pnpm -s openclaw sandbox explain --json includes sandbox.mounts
• Tests cover default mounts + custom bind mount scenario

Test plan

• pnpm -s test src/commands/sandbox-explain.test.ts