harness: execute AtlasCloud plan-delegate task tool calls

[asim]

Root cause:

• Harness (E2E) run https://github.com/micro/go-micro/actions/runs/28708394971 failed in the Provider harnesses (live LLM conformance) job on master at 95e7c387b2160cc320d512c2a6d5961dc3a6405e.
• Only AtlasCloud was configured (ATLASCLOUD_MODEL=minimaxai/minimax-m3); other live providers were skipped for missing API keys.
• In atlascloud / plan-delegate (plan persistence + delegation + tool call), the model response emitted raw MiniMax-tagged tool-call markup for three task_TaskService_Create invocations instead of producing executable tool calls that the agent loop consumed. The notification delegation did run, but no tasks were created, so the harness failed with unexpected side effects: tasks=0 notify=1.
• This was not a provider outage/rate-limit/network timeout: the live model returned a response, the harness continued, and the failure was a deterministic side-effect assertion.

Where:

• The plan-delegate harness path drives the AtlasCloud/minimax-m3 agent through task creation and notification delegation.
• Failure signature: atlascloud / plan-delegate (plan persistence + delegation + tool call): unexpected side effects: tasks=0 notify=1, with the conductor reply containing MiniMax tool markup for task_TaskService_Create calls.

Acceptance criteria:

• The AtlasCloud/minimax-m3 plan-delegate path converts/executes the model's task creation tool calls so Design, Build, and Ship tasks are actually created before notification.
• The stored plan still records completed steps for checking/creating the tasks and delegating notification.
• The plan-delegate harness observes tasks=3 notify=1 (or the harness's expected successful side effects) and exits successfully.
• The provider-conformance harness reports atlascloud / plan-delegate as passed in the next live Harness (E2E) run.

[asim]

recurred

Harness (E2E) run https://github.com/micro/go-micro/actions/runs/28714350727 failed on master at 58b8eb3 in the live provider conformance job. Only AtlasCloud was configured. The atlascloud / plan-delegate (plan persistence + delegation + tool call) harness completed the model dispatch but failed the deterministic side-effect assertion with delegation completed without required notify side effect: notify=0, want 1. This is another occurrence of the existing AtlasCloud plan-delegate side-effect/tool-call execution blocker, not a provider outage/rate-limit/network timeout.