RFE: replace print() with logging in core runtime modules

[cuiyingd]

📝 PR Description

Purpose

Standardize logging in core runtime modules by replacing direct print() calls with the Python logging module. This improves consistency, supports _CI/service deployment, and makes log handling more manageable.

Change Summary

• client.py
  • Added import logging
  • Added logger = logging.getLogger(__name__)
  • Replaced print("Action taken:", action) with logger.info("Action taken: %s", action)
• _embodied_cli.py
  • Added import logging
  • Added logger = logging.getLogger(__name__)
  • Replaced startup/config prints with logger.info(...)
• example_navila_exp.py
  • Added import logging
  • Added logger = logging.getLogger(__name__)
  • Replaced file-not-found print with logger.error(...)
  • Replaced inference result print with logger.info(...)

Benchmark Evidence

• Not applicable for this logging refactor.

Dependencies

None

Environment

• Python 3
• Branch: fix/logging-print-replacement

✔️ Review Checklist

• No breaking changes to core interfaces (VLA API / Dexdata)
• No redundant implementation
• Code follows existing design
• Local validation completed with commands + expected output
• Benchmark evaluation not applicable
• No regressions observed
• No new dependencies
• Merges cleanly on current main

[cuiyingd]

@hbzfeng @yuzhms This is the small change, can you review?