Function buildSplitCallers

buildSplitCallers(plannerOptions, executionOptions?): Promise<{
    plannerCaller: LlmCallerFn;
    executionCaller: LlmCallerFn;
    plannerModel: string;
    executionModel: string;
}>
Build separate planner and execution callers with potentially different providers.
Parameters
- plannerOptions: BuildLlmCallerOptions
  Options for the ToT planning model (strong reasoning).
- Optional executionOptions: BuildLlmCallerOptions
  Options for agent node execution (can be different).
Returns Promise<{
    plannerCaller: LlmCallerFn;
    executionCaller: LlmCallerFn;
    plannerModel: string;
    executionModel: string;
}>
Object with plannerCaller and executionCaller.
Example
```
const { plannerCaller, executionCaller } = await buildSplitCallers(
  { provider: 'claude-code-cli', model: 'claude-opus-4-6' },   // Strong for planning
  { provider: 'openai', model: 'gpt-4o' },                      // Fast for execution
);

const planner = new MissionPlanner({
  llmCaller: executionCaller,
  plannerLlmCaller: plannerCaller,
  plannerModel: 'claude-opus-4-6',
  executionModel: 'gpt-4o',
  ...
});
```
- Defined in src/orchestration/planning/buildLlmCaller.ts:139