[feat] Support agent repetition in AgentRearrange flow

[kyegomez]

Summary

Formally support repeating agents in the flow pattern (e.g., agent1 -> agent2 -> agent1) to enable iterative refinement workflows.

Background

The duplicate agent check in validate_flow() is already commented out (agent_rearrange.py lines 330-333):

# # If the length of the agents does not equal the length of the agents in flow
# if len(set(agents_in_flow)) != len(agents_in_flow):
#     raise ValueError(
#         "Duplicate agent names in the flow are not allowed."
#     )

This suggests the feature was considered but not fully implemented. Agent repetition is valuable for patterns like:

• Iterative refinement: writer -> reviewer -> writer (revise based on feedback)
• Multi-pass analysis: researcher -> analyst -> researcher -> analyst
• Self-correction: coder -> tester -> coder

What needs to happen

1. Ensure conversation context is correct — When an agent appears a second time, it should see its own prior output plus the intermediate agent's feedback, not just re-process the same input.

2. Update team awareness — _get_sequential_awareness() currently finds the first occurrence of an agent name. It should be position-aware so agent1 at step 1 knows it leads to agent2, while agent1 at step 3 knows it follows reviewer.

3. Response dict handling — response_dict[agent_name] = result (line 686) overwrites prior results from the same agent. Use a list or indexed key (e.g., agent1_1, agent1_2).

4. Document the pattern — Add examples to the docstring and docs showing iterative refinement flows.

Acceptance criteria

• Flows like agent1 -> agent2 -> agent1 execute without error
• Each agent invocation gets correct positional awareness
• All outputs from repeated agents are preserved (not overwritten)
• Documentation updated with iterative refinement examples
• Tests cover repeated agent flows