praisonai-platform: Agent endpoints accept any agent_id without workspace ownership check, cross-workspace read/update/delete IDOR

PraisonAI Platform is the platform layer for the PraisonAI multi-agent teams system. Versions prior to 0.1.4 have an* Insecure Direct Object Reference. The agent CRUD endpoints (`GET / PATCH / DELETE /workspaces/{workspace_id}/agents/{agent_id}`) gate access on `require_workspace_member(workspace_id)` only, then resolve `agent_id` through `AgentService.get(agent_id)` which is a primary-key lookup with no workspace constraint. A user who is a member of any workspace `W1` can read, modify, or delete agents that belong to a different workspace `W2` by guessing or harvesting an agent UUID and calling `…/workspaces/W1/agents/<W2-agent-id>`. PraisonAI Platform version 0.1.4 patches the issue.