feat: Adding Chat print node for pretty printing chat conversation between agents

[akhatua2]

📑 Description

Added a pretty printer for agent agent using rich.

✅ Checks

• [x] My pull request adheres to the code style of this project
• [x] All the tests have passed
• [x] Branch name follows type/descript (e.g. feature/add-llm-agents)
• [x] Ready for code review

ℹ Additional Information

Update the goals in the llm_agent.toml file. Then to run this:

uv run aact run-dataflow examples/experimental/llm_agent/llm_agent.toml

Before (Print Node)	After (Chat Print Node)

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 72.88%. Comparing base (7d2ab2f) to head (9c62b90). Report is 18 commits behind head on main.

@@           Coverage Diff           @@
##             main     #250   +/-   ##
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  Coverage   72.88%   72.88%           
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  Files          58       58           
  Lines        2972     2972           
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  Hits         2166     2166           
  Misses        806      806           

Files with missing lines	Coverage Δ
sotopia/experimental/__init__.py	100.00% <100.00%> (ø)
sotopia/experimental/agents/base_agent.py	97.50% <100.00%> (ø)