The agent's id.
Optional baseDir: stringThe folder that holds every agent's workspace; resolveAgentWorkspaceBaseDir by default.
The absolute path of the agent's workspace folder, inside the base folder.
InvalidAgentWorkspaceIdError when the id gives no safe folder name, or its folder would be outside the base folder.
Resolve the full workspace directory for an agent: the folder named by sanitizeAgentWorkspaceId, which must resolve inside the base folder, a second guard should a platform's path rules ever place the folder of an accepted name elsewhere.